Question

What is this one i cant seem to figure it out

Answer 1

Answer:

73

Step-by-step explanation:

Since DA is the diameter, this means that you can divide the circle into two half-circles.  You will solve with the right half-circle.  A half-circle has a 180 total degrees.  Add up the values given and solve for x.

(2x) + (7x - 4) + (85) = 180

2x + 7x - 4 + 85 = 180

9x - 4 + 85 = 180

9x + 81 = 180

9x = 99

x = 11

Now that you have the value of x, solve for m∠CZB.

m∠CZB = 7x - 4

m∠CZB = 7(11) - 4

m∠CZB = 77 - 4

m∠CZB = 73