Evaluate Using the Given Value -a^-2 if a=-5

$- a^{- 2}$ if $a = - 5$

Step 1

Replace the variable $a$ with $- 5$ in the expression.

$- {(- 5)}^{- 2}$

Step 2

Rewrite the expression using the negative exponent rule $b^{- n} = \frac{1}{b^{n}}$ .

$- \frac{1}{{(- 5)}^{2}}$

Step 3

Raise $- 5$ to the power of $2$ .

$- \frac{1}{25}$

Step 4

The result can be shown in multiple forms.

Exact Form:

$- \frac{1}{25}$

Decimal Form:

$- 0.04$