(x-4)^2=25 by taking the square root

x = -1, 9

Step-by-step explanation:

x - 4 = ±5 (positive or negative 5, because (-5)^2 = 25)

x - 4 = 5

x = 9

or

x - 4  = -5

x = -1

x = -1, 9

i'm sure goog can you get that answer

second option

step-by-step explanation:

the measures of a triangle equal 180. use that to find x.

2x+3x+4x=180

9x=180

9x/9=180/9

x=20

now you know x, you know angle a is 40°, angle b is 60°, angle c is 80°.

because angle a is 40°, the first option doesn't work.

because angle b is 60°, the second option does work.

when you add angle a and b, you get 100°. complementary means it equals 90°, so the third option doesn't work.

when you add angle a and c, you get 120°, which is not 100.