Answer:
b
Step-by-step explanation:
∠ BAD = 90° and
∠ DAC + ∠ CAB = ∠ BAD, that is
x + 2x - 30 = 90
3x - 30 = 90 ( add 30 to both sides )
3x = 120 ( divide both sides by 3 )
x = 40 → b
1 3/4d= 14
7/4d = 14
d = 8
Hope this helps! ;)
Angle X is 122°
Because it's a 180° line (supplementary angle thm):
180°-58°=122°