Question

Someone help me please! :D

Answer 1

The angles of a quadrilateral add to 360, so we can solve for x by adding the 4 angle measures together and setting it equal to 360:

90 + 140 + (x - 10) + (x - 20) = 360

Combine like terms:

230 + 2x - 30 = 360

200 + 2x = 360

200 - (200) + 2x = 360 - (200)

2x = 160

Divide both sides by 2:

2x/(2) = 160/(2)

x = 80