In Exercises 1–16, evaluate each algebraic expression for the ...

Question

In Exercises 1–16, evaluate each algebraic expression for the given value or values of the variable(s). (2x+3y)/(x+1), for x=-2 and y=4

Accepted Answer

Welcome back. I'm so glad you're here. We are given an expression. I'll rewrite that bigger. We've got two divided by now. Everything in the parentheses there goes in the denominator. So that's X squared plus Y squared in the denominator and we've got two variables in the X equals one and why equals negative one. And now we want to figure out what's the value of this expression? Alright so this means anywhere we see an X on the left here's one. We're going to replace it with a one and anywhere we see a Y. Here in the expression we're gonna replace it with a negative one. So let's do that. We've got two divided by parentheses. Now instead of X squared it's going to be one Squared plus now instead of why squared? It's going to be negative one squared. And now all we've got our numbers so we can go ahead and use parentheses exponents, multiplication, division, addition and subtraction. That you probably recall from previous lessons Pem does. And the order here is to start with the parentheses. Well we've got parentheses so we're going to work inside those parentheses first. And what do we do inside the parentheses first? Well let's see what's going on. We've got some exponents inside the parentheses. So we are going to go one squared. Well that's one times one. So one squared is one plus now we've got a negative one times a negative one and a negative one times a negative one that's negative one squared gives us one a positive one because those two negatives cancel out when they're multiplied and now we can do the addition inside those parentheses. So one plus one that equals two. Now all that's left for our pem dust is the division two divided by two. That equals one. We look at our answer choices and that matches with answer choice B. Well done, we'll catch you on the next one.

In Exercises 1–16, evaluate each algebraic expression for the given value or values of the variable(s). (2x+3y)/(x+1), for x=-2 and y=4

Key Concepts

Algebraic Expressions

Substitution

Order of Operations

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