### Home > CC3 > Chapter Ch2 > Lesson 2.1.1 > Problem2-9

2-9.

One meaning of the word evaluate is to find the value of an expression. To evaluate, replace a variable with a number and calculate the result. For example, when you are asked to evaluate the expression $4x-2$ when $x=-7$, you would put $-7$ in place of the variable and calculate: $4·(-7)-2=-30$.

Evaluate the expressions below for the given values of $x$ and $y$.

Rewrite the expression with the number in place of the variable and simplify if possible.

1. $\frac{6}{x}+9$ if $x=3$

$\frac{ 6 }{(3) } + 9 =$

Remember $\frac{6}{3}$ is the same as $6$ divided by $3$.

$11$

1. $8x-3+y$ if $x=2$ and $y=1$

$8(2)-3+(1)$

Try evaluating this one on your own.

1. $2xy$ if $x=5$ and $y=-3$

$2(5)(-3)=10(-3)$

$-30$

1. $2x^2-y$ if $x=3$ and $y=8$

$2(3)^2-(8)$

Try evaluating this one on your own. You have been given a head start.