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Need help on this question please-example-1

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Answers:

x = 13 and y = 11

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Step-by-step explanation:

Check out the diagram below. I've added in the label (4x+13) degrees to the angle adjacent to the (9x-2) degree angle. This is valid due to corresponding angles being congruent when we have parallel lines like this.

The two angles form a 180 degree straight angle

(4x+13) + (9x-2) = 180

4x+13 + 9x-2 = 180

(4x+9x) + (13-2) = 180

13x + 11 = 180

13x+11-11 = 180-11 .... subtracting 11 from both sides

13x = 169

13x/13 = 169/13 .... dividing both sides by 13

x = 13

We can verify this by noticing that

4x+13 = 4*13+13 = 65

9x-2 = 9*13-2 = 115

So, (4x+13)+(9x-2) = (65)+(115) = 180, showing the two angles are supplementary.

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The angles (9x-2) and (6y-1) are also a linear pair. They are adjacent and supplementary

Let's use x = 13 to find the value of y

(9x-2) + (6y-1) = 180

9x-2+6y-1 = 180

9x+6y-3 = 180

9*13+6y-3 = 180 .... plug in x = 13

117+6y-3 = 180

6y+114 = 180

6y+114-114 = 180-114 .... subtract 114 from both sides

6y = 66

6y/6 = 66/6 ...... divide both sides by 6

y = 11

To help confirm,

6y-1 = 6*11-1 = 65

which adds onto the (9x-2) = 115 degree angle to get 180.

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Side note: as an alternative, you can solve 4x+13 = 6y-1 to get the same y value. This is because alternate exterior angles are congruent when we have parallel lines like this.

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