Question

What is the measure of a

Answer 1

In a triangle, we know that the sum of the angles must equal to 180°.

And we also know that two supplementary angles must equal to 180°.

That being said, we are given the value of ∠C as 75°.

In order to solve for ∠B, we must first calculate it. ∠B is part of a supplementary angle, which we know the other angle is equal to 122°. In order to find ∠B, we must subtract 122° from 180°:


`180-122=58`

So now we know that ∠B is equal to 58°.

So we know the values of two angles of the triangle. In order to solve for the third angle, we must subtract the two known angles values from 180°:


`180-75-58=47`

And now we know that ∠A is equal to 47°.

Answer 2

The measure of a is 47