Asap 25 pts + brainliest to right/best answer
i have no idea how to answer this?

c 4

Step-by-step explanation:

x^2 -4x

b is -4

Divide by 2 and then square it

-4/2 =2

2^2 =4

We need to add 4

∠acb = 8°

step-by-step explanation:

∠xba lies on the circle and is half the measure of the intercepted arc ax

hence

measure of arc ax = 2 × 42° = 84°

∠acb is outside the circle and is

∠acb = (arcab - arcax ), hence

∠acb = 0.5 (100 - 84) = 0.5 × 16° = 8°