Question

If x^2+4=29, then x^2-4=?

Answer 1

21

Explanation:

The first step is to solve for x. I did this by bringing 4 to one side and combining like terms.

x^2=29-4

x^2=25

x=sqrt25

x=5

Then I plugged x into the second equation.

5^2-4=

25-4=21

Obviously there are easier ways to go about this problem, but this is the way I feel comfortable with.

Hope this helps!

~gloriouspurpose~

Answer 2

21

Explanation:

x^2+4=29

Subtract 8 from each side

x^2+4-8=29-8

x^2 -4 = 21