Respuesta :

Since angles EFA, AFB, and BFC lie on a straight line, then they must add up to 180° (angle sum of a straight line)

So, 7x + 4 + 8x + 6 + 6x + 2 = 180
21x + 12 = 180
21x = 168
x = 8
sdmatera
We are given three angle values, all which have the variable x in them. All three of these angles happen to be suplementary, or add to 180. So we can write a formula where we set the sum of all three angles equal to 180 and solve for x.

(6x+2)+(8x+6)+(7x+4)=180 (combine like terms)
21x+12=180 (subtract 12 from both sides)
21x=168 (divide both sides by 21)
X=8

Hope this helps