In a geometric diagram, A and B are complementary, and they form a straight line with

C. If m A = x°, m B = (2x)° , and m C = 90° , what is the measure of B
• 30°
O 90°
• 180°
O 60°

1 answer

In a straight line, the sum of the angles is always 180°. Since C is a right angle (90°), the sum of angles A and B must be equal to 180° - 90° = 90°.

Given that A is x° and B is 2x°, we can write the equation:

x° + 2x° = 90°

Combining like terms, we get:

3x° = 90°

Dividing both sides by 3, we get:

x° = 30°

Therefore, angle B is 2x° = 2(30°) = 60°.

The measure of B is 60°.