Evaluate Using the Given Value 8p+3q-18 when p=1/2 and q=7

$8 p + 3 q - 18$ when $p = \frac{1}{2}$ and $q = 7$

Replace the variable $p$ with $\frac{1}{2}$ in the expression.

$8 (\frac{1}{2}) + 3 q - 18$

Replace the variable $q$ with $7$ in the expression.

$8 (\frac{1}{2}) + 3 (7) - 18$

Simplify each term.

Cancel the common factor of $2$ .

Factor $2$ out of $8$ .

$2 (4) \frac{1}{2} + 3 (7) - 18$

Cancel the common factor.

$2 \cdot 4 \frac{1}{2} + 3 (7) - 18$

Rewrite the expression.

$4 + 3 (7) - 18$

Multiply $3$ by $7$ .

$4 + 21 - 18$

Simplify by adding and subtracting.

Add $4$ and $21$ .

$25 - 18$

Subtract $18$ from $25$ .

$7$