Question

Find the measure of arc DF (with an explanation of how to solve please!)

Answer 1

Answer:

mDF = 90°

(Assuming arc mCE is 5x + 10)

Step-by-step explanation:

When we have two chords crossing in a circle, there is a property where the angle in the cross point is equal half the sum of the corresponding arcs.

So in this case, we have:

70° = (mCE + mDF)/2

Assuming mCE is 5x + 10, we have:

70 = (5x + 10 + 11x + 2)/2

70 = (16x + 12)/2

70 = 8x + 6

8x = 64

x = 8

So the arc mDF is:

mDF = 11x + 2 = 11 * 8 + 2 = 90°