Find the value of x.

x=11

Step-by-step explanation:

The sum of the angles of a triangle is 180

We know the angle with a box is 90

90 + 5x-2  + 3x+4 = 180

Combine like terms

8x +92 = 180

Subtract 92 from each side

8x+92-92 = 180-29

8x = 88

Divide each side by 8

8x/8 = 88/8

x = 11

answer: i believe c. is the answer sorry if i am wrong

step-by-step explanation:

according to the triangle sum theorem, all the angles in a triangle must add up to 180 degrees. if we know one angle is already 90, we do 180-90=90. the other 2 angles must add up to 90, exactly.

step-by-step explanation: