The sum of two adjacent angles is 100°, so we can write the equation ∠1 + ∠2 = 100°.
Substituting the given measures, we get 20° + (3x + 15)° = 100°.
Simplifying, we have 3x + 35 = 100.
To solve for x, we subtract 35 from both sides of the equation:
3x = 65.
The equation that can be used to solve for x is 3x + 35 = 100.
Therefore, the correct answer is D. 3x + 35 = 100.
Two adjacent angles have a sum of 100°. The angles have measures ∠1 = 20° and ∠2 = (3x + 15)°. What equation can be used to solve for x?
A. 3x+115=20
B. 3x−20=100
C. 3x−100=20
D. 3x+35=100
1 answer