20 B PLEASE HELP!! Question 12

The number is -12

Step-by-step explanation:

(x+5) *8 = -56

Divide each side by 8

(x+5)*8/8 = -56/8

x+5 = -7

Subtract 5 from each side

x+5-5 = -7-5

x = -12

X=12

I have had a test on this i forgot my explanation tho.

since your problem is x^4 = 81, what you have to undeo is the "to the fourth power" part.

the inverse (opposite operation) of "to the fourth power" is "to the fourth root".

  (x^4) ^ ¼   = 81 ^ ¼  

  81 = 3^4     so (3 ^ 4) ^ ¼   =   3 ^ 1   = 3

by hand: (3 ^ 4) ^ ¼   =   3 ^ (4 x ¼) = 3 ^ 1   = 3   (when you take a power to a power, multiply the exponents.)

or, do it by calculator. one way of finding the fourth root is to use ^ (1/4)

step-by-step explanation:

-232

step-by-step explanation: