We are given a straight line PQ with point O on it. From point O, two rays OS and OR go upward, forming three angles along the straight line:
- Angle POS = 5x + 4°
- Angle SOR = x - 2°
- Angle ROQ = 3x + 7°
Since PQ is a straight line, the total angle from P to Q through O must be
180 degrees.
So we can write an equation:
> (5x + 4) + (x - 2) + (3x + 7) = 180
Now let’s combine like terms step by step.
First, add all the x terms:
5x + x + 3x =
9x
Then add all the constant numbers:
4 - 2 + 7 =
9
So the equation becomes:
> 9x + 9 = 180
Now subtract 9 from both sides:
> 9x = 171
Now divide both sides by 9:
> x = 19
Let’s double-check by plugging x = 19 back into each angle:
- 5x + 4 = 5(19) + 4 = 95 + 4 =
99°
- x - 2 = 19 - 2 =
17°
- 3x + 7 = 3(19) + 7 = 57 + 7 =
64°
Add them up: 99 + 17 + 64 =
180° → Perfect! It checks out.
Final Answer:
19
Parent Tip: Review the logic above to help your child master the concept of complementary and supplementary angles word problems worksheet.