Answer:
x = 12
Explanation:
The sum of angles in a triangle is 180°
Thus,
(x + 20) + (10x) + (x + 16) = 180°
Collect like terms
x + 10x + x + 20 + 16 = 180°
12x + 36 = 180°
12x = 180 - 36
12x = 144
Divide both sides by 12
x = 144 ÷ 12
x = 12
Substitute the value of x into the question
Therefore,
x + 20 = 12 + 20
= 32°
10x = 10(12)
= 120°
x + 16 = 12 + 16
= 28°