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
?(1 point)
Responses

180°
180 degrees

60°
60 degrees

30°
30 degrees

90°
90 degrees

We know that the sum of the measures of two complementary angles is 90 degrees. Therefore, since ∠A and ∠B are complementary, we can write the equation:

m∠A + m∠B = 90

Plugging in the given values, we have:

x + 2x = 90

Combining like terms, we get:

3x = 90

Dividing both sides by 3, we find:

x = 30

Since we are looking for the measure of ∠B, which is 2x, we have:

m∠B = 2x = 2(30) = 60 degrees

Therefore, the measure of ∠B is 60 degrees. The correct answer is:

60°