Someone help me with this

81

Step-by-step explanation:

Any number, wether it is negative or postive, will always be postive when there is a even exponent.

In this case, we have a -9, and a exponent thats 2.

Since 2 is a even number, -9^2 will be a postive value.

Now, what is the actual value of this?

Well, a exponent of 2 basiclly means 2 numbers being multiplied together.

Or in this case, 2 negative 9s being multiplied together.

THis will be:

-9*-9

=

As I said above, a even exponent makes a negative number postive.

You see here that a negative 9 is being multiplied by -9. When two negative numbers multiply together, they make a postive.

THis is why a even exponent makes a postive.

Hope this helps!

step-by-step explanation:

1. 22

2. 1

3. 7

4. 18

step-by-step explanation

e2020 got it right