## leroysgurl15 2 years ago find the value of x.

1. leroysgurl15

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2. Georgia_peach

are these in degrees?

3. hwtrain

Is that a right angle?

4. leroysgurl15

yeah

5. leroysgurl15

yeah they are in degrees

6. bcdrane42

3x-9=90 solving for x gives x=33 making the second one 40 degrees

7. bcdrane42

That is if that 3x-9 is the angle of the vertical line to the ground and the angle is "right"

8. leroysgurl15

3x-9 is a right angle

9. Directrix

@bcdrane42 Would it be correct to write: 3x - 9 + x + 7 = 90 because perpendicular lines meet to form right angles and right angles have a measure of 90. There's one more theorem that goes with that.

10. Directrix

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11. hwtrain

Well you have to combine the 3x-9 and x+7 = to 90 3x-9+x+7=90 combine like terms 4x=92 Divide to get x by itself x=23 Then plug that back into x to get the two other angles.

12. leroysgurl15

so i would go 3*23-9 = 60 23+7=30

13. hwtrain

Yep should be that.

14. bcdrane42

Actually it looks like 3x-9 represents the angle between the vertical line and the 2ND LINE, not the ground. That would make what directx says correct: 3x-9+x+7=90 solving for x gives you: 23

15. Georgia_peach

right angels give you 90 derees so it should add up to 90 degrees