Find the measure of ∠NED, not ∠CED.

Step-by-step explanation:

By exterior angle theorem:

(9x - 8)° = (5x - 10)° + 50°

(9x - 8)° = (5x - 10 + 50)°

(9x - 8)° = (5x + 40)°

9x - 8 = 5x + 40

9x - 5x = 40 + 8

4x = 48

x = 48/4

x = 12

(9x - 8)° = (9*12 - 8)° = (108 - 8)° = 100°

(Linear pair angles)

Measure of Exterior Angle of a triangle is equal to the sum of measures of two opposite interior angles .

From above statement we have :

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option 3 . (5x + 1) - (-10x + 6)

step-by-step explanation:

option 1 :

(4x + 3) + (-9x + 4)

or 4x+3 -9x + 4

or -5x + 7

option 2

(x - 2) - (6x - 9)

or x-2-6x + 9

or -5x + 7

option 3

(5x+ + 6)

or 5x + 1 + 10x -6

or 15x -5

option 4

-4x+2x+7-3x

-7x + 2x + 7

-5x + 7

hence only option 3 did   not satisfy the given simplify expression.

the answer is c: divide the arc's degree measure by 360°, then multiply by the circumference of the circle.