we know that
The sum of the internal angles in the triangle must be degrees
see the attached figure with letters to better understand the problem
Step
<u>Find the measure of the angle x</u>
In the triangle ABC
solve for x
therefore
<u>the answer Part a) is</u>
the measure of angle x is
Step
<u>Find the measure of the angle z</u>
we know that
--------> by supplementary angles
substitute the value of x
therefore
<u>the answer Part b) is</u>
the measure of angle z is
Step
<u>Find the measure of the angle y</u>
In the triangle ACD
solve for y
therefore
<u>the answer Part c) is</u>
the measure of angle y is