Answer:
x = -3
Step-by-step explanation:
Notice that the addition of angle <CDH plus angle <HDE have to give the measure of angle <CDE (which is 144 degrees as stated in the problem)
Then, we can say in equation form:
<CDH + <HDE = 144
replacing with their expressions in terms of x:
x + 93 + 57 + x = 144
solving for x:
2 x + 150 = 144
2 x = 144 - 150
2 x = - 6
x = -3
