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Help Please I have 7 of these to do within 30 minutes and i dont get them

Help Please I have 7 of these to do within 30 minutes and i dont get them-example-1
User Kechap
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1 Answer

3 votes

Answer:

angle JKL is 22°

Explanation:

You want the measure of exterior angle JKL represented by (5x-3)°, given that the remote interior angles of ∆IJK are I = (2x +8)° and J = (x -1)°.

Exterior angle

The exterior angle is equal to the sum of the remote interior angles:

angle JKL = angle I + angle J

5x -3 = (2x +8) +(x -1)

5x -3 = 3x +7 . . . . . . . . . simplify

2x = 10 . . . . . . . . . . . add 3-3x

x = 5 . . . . . . . divide by 2

5x -3 = 5(5) -3 = 22 . . . . . degrees

Angle JKL is 22 degrees.

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Additional comment

It is helpful to draw a figure. The attached figure is not to scale, but the angle measures are appropriately labeled.

The unlabeled interior angle at K is supplementary to the labeled exterior angle there. That same interior angle is also supplementary to the sum of the other two interior angles, since the sum of all the angles is 180°. Two angles supplementary to the same angle are congruent. This means the exterior angle JKL is congruent to the sum of the two marked interior angles. It's a simple relation, easy to derive, and useful to remember.

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Help Please I have 7 of these to do within 30 minutes and i dont get them-example-1
User Downeyt
by
7.7k points