Angles on a straight line add up to 180°
This means we can say that:
(5x + 20) + (4x +25) = 180
Now we have an equation that we can solve:
(5x + 20) + (4x +25) = 180
9x + 45 = 180 (we collected the terms : 4x + 5x = 9x, and 20 + 25 = 45)
9x = 135 (we subtracted both sides by 45, to get the x values alone on one side)
x = 15 (we divided both sides by 9, to get what just x is)
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Now that we know the value of x, we can substitute it into the equations given in the diagram:
5x + 20 = 5 * 15 + 20
= 95°
4x + 25 = 4 * 15 + 25
= 85°
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Answer:
So the measure of the two angles are:
A) 95° and 85
