Skip to main content
Indietro

Intermediate Algebra Exam 1 Study Guidance (Ch 2 & 3)

Guida di studio - Note intelligenti

Appunti personalizzati basati sui tuoi materiali, ampliati con definizioni chiave, esempi e contesto.

Q1. Translate the sentence: "x is 25% of 200." Which equation correctly represents this?

Background

Topic: Percent Problem Solving

This question tests your ability to translate a verbal statement involving percentages into an algebraic equation.

Key Terms and Formulas:

  • Percent: A way to express a number as a fraction of 100.

  • "of" in math usually means multiplication.

  • 25% as a decimal is 0.25.

Step-by-Step Guidance

  1. Identify the unknown: Let represent the value we are solving for.

  2. Translate "25% of 200" into mathematical terms: .

  3. Set up the equation: .

  4. Check the answer choices to see which matches this setup.

Try solving on your own before revealing the answer!

Final Answer: x = 0.25 × 200

The correct equation is . This directly translates the sentence "x is 25% of 200."

Q2. Why does the equation |x| = -3 have no real solutions?

Background

Topic: Absolute Value Equations

This question tests your understanding of the definition and properties of absolute value.

Key Terms and Formulas:

  • Absolute value: is always non-negative (never less than zero).

  • There is no real number whose absolute value is negative.

Step-by-Step Guidance

  1. Recall the definition: represents the distance from zero, which is always zero or positive.

  2. Consider what it would mean for to have a solution.

  3. Ask: Is there any real number such that its absolute value is negative?

Try solving on your own before revealing the answer!

Final Answer: Because absolute value represents distance, which cannot be negative, no real x has distance -3 from zero.

The correct answer is: b. Because absolute value represents distance, which cannot be negative, no real x has distance -3 from zero.

Q3. Solve the inequality: x - 7 > 2

Background

Topic: Linear Inequalities in One Variable

This question tests your ability to solve a basic linear inequality.

Key Terms and Formulas:

  • Linear inequality: An inequality involving a linear expression.

  • To solve, isolate the variable using inverse operations.

Step-by-Step Guidance

  1. Start with the inequality: .

  2. Add 7 to both sides to isolate .

  3. Simplify the right side after addition.

Try solving on your own before revealing the answer!

Final Answer: x > 9

After adding 7 to both sides, you get .

Q4. If -2x < 6, what is the correct solution for x after isolating the variable?

Background

Topic: Absolute Value Inequalities / Linear Inequalities

This question tests your ability to solve inequalities, especially when dividing by a negative number.

Key Terms and Formulas:

  • When you multiply or divide both sides of an inequality by a negative number, you must reverse the inequality sign.

Step-by-Step Guidance

  1. Start with .

  2. Divide both sides by to solve for .

  3. Remember to reverse the inequality sign when dividing by a negative.

Try solving on your own before revealing the answer!

Final Answer: x > -3

Dividing both sides by -2 and reversing the inequality gives .

Q5. Translate: "There are eight more nickels than dimes," if d = number of dimes and n = number of nickels.

Background

Topic: Mixture Problem Solving / Translating Sentences to Equations

This question tests your ability to write an equation based on a verbal statement about quantities.

Key Terms and Formulas:

  • "Eight more" means you add 8 to the number of dimes to get the number of nickels.

Step-by-Step Guidance

  1. Let be the number of dimes and the number of nickels.

  2. "Eight more nickels than dimes" means nickels = dimes + 8.

  3. Write this as an equation: .

Try solving on your own before revealing the answer!

Final Answer: n = d + 8

The correct translation is .

Q6. Solve: 4(x - 2) = 3x + 5. Which value of x satisfies the equation?

Background

Topic: Solving Linear Equations

This question tests your ability to solve a linear equation for the variable x.

Key Terms and Formulas:

  • Distributive property:

  • Combine like terms and isolate x.

Step-by-Step Guidance

  1. Expand the left side: .

  2. Set the equation: .

  3. Subtract from both sides to get all x terms on one side.

  4. Add 8 to both sides to isolate x.

Try solving on your own before revealing the answer!

Final Answer: x = 13

After simplifying and isolating x, you find .

Q7. Which symbol denotes the intersection of sets A and B?

Background

Topic: Set Operations and Compound Inequalities

This question tests your knowledge of set notation, specifically the symbol for intersection.

Key Terms and Formulas:

  • Intersection: The set of elements common to both sets.

  • Symbol:

Step-by-Step Guidance

  1. Recall that intersection means elements in both sets.

  2. Identify the symbol for intersection among the choices.

Try solving on your own before revealing the answer!

Final Answer: A ∩ B

The intersection of sets A and B is denoted by .

Q8. Which phrase signals you should introduce a variable? Sentence: "The number of apples a student picks."

Background

Topic: Translating Sentences to Equations

This question tests your ability to identify the unknown quantity in a word problem.

Key Terms and Formulas:

  • Unknown quantity: The part of the sentence that is not specified and needs a variable.

Step-by-Step Guidance

  1. Look for phrases that describe an unknown amount.

  2. "The number of apples" is the quantity we don't know and should represent with a variable.

Try solving on your own before revealing the answer!

Final Answer: "The number" or "the number of apples"

This phrase signals the unknown quantity to represent with a variable.

Q9. Simplify and solve: -3(2x + 5) + 4x = 7

Background

Topic: Solving Linear Equations

This question tests your ability to use the distributive property and combine like terms to solve for x.

Key Terms and Formulas:

  • Distributive property:

  • Combine like terms and isolate x.

Step-by-Step Guidance

  1. Expand to .

  2. Add to get .

  3. Combine like terms: .

  4. Add 15 to both sides to isolate the x term.

Try solving on your own before revealing the answer!

Final Answer: x = -11

After simplifying and isolating x, you find .

Q10. The formula for the volume of a triangular prism is V = (1/2)bhL. If b = 6 cm, h = 8 cm, and L = 10 cm, compute V.

Background

Topic: Formulas

This question tests your ability to substitute values into a geometric formula and compute the result.

Key Terms and Formulas:

  • Volume of a triangular prism:

Step-by-Step Guidance

  1. Write the formula: .

  2. Substitute , , into the formula.

  3. Multiply and first, then multiply by .

  4. Multiply by to get the final volume.

Try solving on your own before revealing the answer!

Final Answer: 240 cm³

Substituting the values gives cm³.

Q11. Given 5x - 10y ≤ 20, write the boundary line in slope-intercept form.

Background

Topic: Linear Inequalities in Two Variables

This question tests your ability to rewrite a linear equation in slope-intercept form ().

Key Terms and Formulas:

  • Slope-intercept form:

Step-by-Step Guidance

  1. Start with (boundary line).

  2. Subtract from both sides: .

  3. Divide both sides by to solve for .

Try solving on your own before revealing the answer!

Final Answer: y = (1/2)x - 2

After rearranging, the boundary line is .

Q12. Which mapping diagram corresponds to the ordered pairs (1, 2), (3, 4), and (1, 5)?

Background

Topic: Introduction to Relations and Functions

This question tests your understanding of mapping diagrams and how ordered pairs are represented.

Key Terms and Formulas:

  • Mapping diagram: Shows how each input (x) is paired with an output (y).

Step-by-Step Guidance

  1. List the ordered pairs: (1, 2), (3, 4), (1, 5).

  2. Notice that 1 is paired with both 2 and 5, and 3 is paired with 4.

  3. Look for a diagram where 1 points to both 2 and 5, and 3 points to 4.

Try solving on your own before revealing the answer!

Final Answer: A diagram where 1 points to 2 and 5, and 3 points to 4.

This matches the mapping for the given ordered pairs.

Q13. A line passes through (3, 5) and (0, -2). What is the y-intercept?

Background

Topic: Slope-Intercept Form

This question tests your ability to find the y-intercept from two points on a line.

Key Terms and Formulas:

  • y-intercept: The value of y when x = 0.

Step-by-Step Guidance

  1. Recall that the y-intercept is the y-value when x = 0.

  2. Look at the given points: (3, 5) and (0, -2).

  3. Identify which point has x = 0.

Try solving on your own before revealing the answer!

Final Answer: -2

The y-intercept is -2, from the point (0, -2).

Q14. What does the notation f(x) represent in the context of functions relating x and y?

Background

Topic: Function Notation

This question tests your understanding of function notation and its meaning.

Key Terms and Formulas:

  • Function notation: means "the value of the function f at x" or "the output y for input x".

Step-by-Step Guidance

  1. Recall that is read as "f of x".

  2. It represents the output value when x is the input.

  3. It does not mean multiplication or a new variable.

Try solving on your own before revealing the answer!

Final Answer: The output y corresponding to the input x

represents the output value for the input x in the function f.

Q15. For 4x + 2y = 8, if x = 1, what is the corresponding y and which point do you plot?

Background

Topic: Graph Linear Equations Using Intercepts

This question tests your ability to substitute a value for x and solve for y in a linear equation.

Key Terms and Formulas:

  • Substitute x = 1 into the equation and solve for y.

Step-by-Step Guidance

  1. Start with .

  2. Substitute into the equation: .

  3. Simplify and solve for y.

Try solving on your own before revealing the answer!

Final Answer: (1, 2)

When , , so the point to plot is (1, 2).

Q16. What is the best definition of an ordered-pair solution to a two-variable linear equation?

Background

Topic: Graph Linear Equations in Two Variables

This question tests your understanding of what it means for an ordered pair to be a solution to a linear equation.

Key Terms and Formulas:

  • Ordered pair:

  • Solution: When substituted into the equation, both sides are equal.

Step-by-Step Guidance

  1. Recall that a solution to a linear equation in two variables is a pair .

  2. Substitute into the equation to check if it makes the equation true.

  3. The correct definition will mention both substitution and equality.

Try solving on your own before revealing the answer!

Final Answer: An ordered pair (x, y) that, when substituted into the equation, makes both sides equal; it corresponds to the single point with coordinates x and y on the coordinate plane.

This is the precise definition of an ordered-pair solution.

Q17. Find the slope of the line through (4, -2) and (1, 4) using the slope formula.

Background

Topic: Slope of a Line

This question tests your ability to use the slope formula to find the slope between two points.

Key Terms and Formulas:

  • Slope formula:

Step-by-Step Guidance

  1. Label the points: and .

  2. Plug the values into the slope formula: .

  3. Simplify the numerator and denominator separately.

Try solving on your own before revealing the answer!

Final Answer: -2

The slope is .

Q18. Which statement correctly describes the roles of the x-axis and y-axis in the Cartesian plane?

Background

Topic: The Rectangular Coordinate System

This question tests your understanding of the axes in the Cartesian (rectangular) coordinate system.

Key Terms and Formulas:

  • x-axis: Horizontal axis

  • y-axis: Vertical axis

Step-by-Step Guidance

  1. Recall that the x-axis runs left to right (horizontal) and the y-axis runs up and down (vertical).

  2. The origin is where the axes intersect (0, 0).

  3. Negative and positive values are included on both axes.

Try solving on your own before revealing the answer!

Final Answer: The x-axis is horizontal and represents left–right movement, while the y-axis is vertical and represents up-down movement. Together, they form the rectangular coordinate system.

This is the correct description of the axes in the Cartesian plane.

Q19. Write the equation of the line in point-slope form with slope m = 3 passing through (4, -1).

Background

Topic: Point Slope Form

This question tests your ability to write the equation of a line given a point and a slope.

Key Terms and Formulas:

  • Point-slope form:

Step-by-Step Guidance

  1. Identify the point and the slope .

  2. Plug these values into the point-slope formula: .

  3. Simplify to .

Try solving on your own before revealing the answer!

Final Answer: y + 1 = 3(x - 4)

This is the equation in point-slope form for the given point and slope.

Pearson Logo

Study Prep