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°
The measure of arc DF should be 90 degrees.
Here we assume arc mCE should be 5x + 10
Since mDF = 90°
Also we know that at the time when two chords should be crossing in a circle so the angle in the cross point should be equivalent to the half the sum of the arcs
So base don this.
[tex]70 = (mCE + mDF)\div 2\\\\70 = (5x + 10 + 11x + 2)\div 2\\\\70 = (16x + 12)\div 2[/tex]
70 = 8x + 6
8x = 64
x = 8
Now the arc mDF is:
mDF = 11x + 2
= 11 (8) + 2
= 90°
Hence, The measure of arc DF should be 90 degrees.
Learn more about an arc here: https://brainly.com/question/3401487
