Answer: 7
Explanation:
m∠ABC = 40°. Since BD is an angle bisector (divides the angle into two congruent angles), then m∠ABD = 20° and m∠CBD = 20°
ABD = 20 and ABD = 3x - 1
⇒ 20 = 3x - 1
⇒ 21 = 3x
⇒ 7 = x
Check:
CBD = 20 and CBD = 34 - 2x
⇒ 20 = 34 - 2x
⇒ -14 = -2x
⇒ 7 = x