Question

Please help i have a test tomorrow and i dont know how to do this

Answer 1

90 - 2x

Explanation:

Angle A and B are both equal as both connect to the middle of the circle

ABO =
`x`

BAO =
`x`

Look at the diagram I attached

Angle ABC is =
`x+90`

Angle BAC =
`x`

Total Angle in a Triangle = 180

`x + 90 + x + ACB = 180`

`180 - 90 - 2x = ACB`

`ACB = 90 - 2x`