Question

Translate the scenario below to a linear equation, then solve.

Answer 1

Answer:  x + 2x + x-40 = 180

First angle= 55º

Second angle= 110º

Third angle= 15º

​Step-by-step explanation:  The sum of the angles of a triangle is 180º

Take the values given and  use x as the unknown first angle. then create terms for the other two angles based on that:

The second angle of a triangle is double the first angle  becomes 2x

The third angle is 40 less than the first angle becomes x-40

x + 2x + x-40 = 180  Solve by adding like terms . x + 2x + x = 4x

4x -40 = 180   Add 40 to both sides to "cancel" the -40 on the left

4x + 40 -40 = 180 + 40   becomes  

4x = 220  Divide both sides by 4 to "cancel" the 4 on the left side

4x/4 = 220/4

x = 55   This is the first angle. Substitute 55 for the  "x" in the original terms

2(55) = 110   The second angle

(55) -40 = 15   the third angle