Question

The interior angles formed by the sides of a quadrilateral have measures that sum to 360°.

Answer 1

2x+2x+124+124 = 360
4x+248 = 360
4x = 360 - 248
4x = 112
x = 112/4
x = 28

answer x = 28

Answer 2

Let

$angle 1=2x$°

$angle 2=2x$°

$angle 3=124$°

$angle 4=124$°

we know that

The interior angles formed by the sides of a quadrilateral have measures that sum to 360°

so

$angle 1+angle 2+angle 3+angle 4=360$°

$2x+2x+124+124=360\\ 4x+248=360\\ 4x=112\\ x=28degrees$

therefore

the answer is

$x=28degrees$