Answer:
∠ 3 = 25°
Step-by-step explanation:
The sum of the 3 angles 85, 2x and x - 10 are a straight angle = 180°
85 + 2x + x - 10 = 180, that is
3x + 75 = 180 ( subtract 75 from both sides )
3x = 105 ( divide both sides by 3 )
x = 35
Thus x - 10 = 35 - 10 = 25
∠ 3 and x - 10 are Alternate angles and congruent, thus
∠ 3 = 25°
