Question

Q9.

A, B and C are three points on a
The radil from A, B and C are shown.
is AC a diameter of the circle?

Answer 1

Explanation:

If AC is a diameter then the angle (5x + 40) = 180 degrees.

Total angles in a circle = 360 degrees, so:

x + 2(2x + 20) + 5x + 40 = 360

x + 4x + 5x + 40 + 40 = 360

10x = 360 - 80 = 280

x = 28.

So the angle 5x + 40

= 5(28) + 40

= 140 + 40

= 180.

So AC is the diameter.