### Home > AC > Chapter 2 > Lesson 2.1.9 > Problem2-90

2-90.

Evaluate the expressions below for the given values.

1. $6m + 2n^2\ \text{for}\ m = 7\ \text{and}\ n = 3$

Substitute the given values for the variables $m$ and $n$.
$6(7) + 2(3^2)$

Simplify the expression.
$42 + 18 = 60$

$60$

1.  $\frac{5x}{3}-2\ \text{for}\ x=-18$

Substitute $−18\ \text{for}\ x$ in the expression. Then simplify.

1.  $(6x)^2-\frac{x}{5}\ \text{for}\ x=10$

After substituting $10\ \text{for}\ x$, the expression becomes:

$(6\cdot10)^{2}-\frac{10}{5}$

Simplify. Be sure to multiply the $6$ and $10$ before squaring!

1. $(k − 3)(k + 2)\ \text{for}\ k = 1$

Replace each $k\ \text{with}\ 1$, and then simplify the expression.

$−6$