Respuesta :

Answer:

C) 3x=54

Step-by-step explanation:

Angle ABD is a straight angle, which means it measures 180 degrees.

Angles ABC & CBD are linear pairs. (The two of them add up to 180°)

ABD is a right angle (90 degrees)

The straight angle (180) minus the right angle (90) equals 90 degrees.

x+2x+2x=90°

Combine like terms

5x=90°

divide by 5 on both sides

x=18

18×3=54

C

Hope this helps :-)