For each graph, determine whether y is a function of x. Give the domain and range of each relation.
Table of contents
- 0. Review of Algebra4h 18m
- 1. Equations & Inequalities3h 18m
- 2. Graphs of Equations1h 43m
- 3. Functions2h 17m
- 4. Polynomial Functions1h 44m
- 5. Rational Functions1h 23m
- 6. Exponential & Logarithmic Functions2h 28m
- 7. Systems of Equations & Matrices4h 5m
- 8. Conic Sections2h 23m
- 9. Sequences, Series, & Induction1h 22m
- 10. Combinatorics & Probability1h 45m
2. Graphs of Equations
Two-Variable Equations
Problem 25
Textbook Question
Determine whether each equation defines y as a function of x. y = 6 -x2
Verified step by step guidance1
Recall the definition of a function: for each input value of x, there must be exactly one output value of y.
Look at the given equation: \(y = 6 - x^{2}\).
For any value of x, calculate the right side \$6 - x^{2}$ to find the corresponding y value.
Since squaring x (\(x^{2}\)) always gives a non-negative result and subtracting it from 6 gives a unique y for each x, there is only one y for each x.
Therefore, the equation defines y as a function of x because each x corresponds to exactly one y.
Verified video answer for a similar problem:This video solution was recommended by our tutors as helpful for the problem above
Video duration:
55sPlay a video:
Was this helpful?
Key Concepts
Here are the essential concepts you must grasp in order to answer the question correctly.
Definition of a Function
A function is a relation where each input (x-value) corresponds to exactly one output (y-value). This means for every x, there is only one y. Understanding this helps determine if an equation defines y as a function of x.
Recommended video:
Graphs of Common Functions
Evaluating Equations for Function Criteria
To check if an equation defines y as a function of x, substitute values of x and see if y has a unique value. If each x produces only one y, the equation represents a function.
Recommended video:
Evaluating Composed Functions
Quadratic Functions and Their Graphs
The equation y = 6 - x² is a quadratic function, which graphs as a parabola opening downward. Since for each x there is only one y, quadratic equations like this define y as a function of x.
Recommended video:
Graphs of Logarithmic Functions
Watch next
Master Equations with Two Variables with a bite sized video explanation from Patrick
Start learningRelated Videos
Related Practice
Textbook Question
951
views
