SOLUTION: Hello. I am not sure how the book gets an answer of 12 for the following question. Can someone please help. Thanks. Quadrilateral QUAD is a rectangle. Find the value of x.

Algebra ->  Rectangles -> SOLUTION: Hello. I am not sure how the book gets an answer of 12 for the following question. Can someone please help. Thanks. Quadrilateral QUAD is a rectangle. Find the value of x.       Log On


   



Question 400357: Hello.
I am not sure how the book gets an answer of 12 for the following question.
Can someone please help. Thanks.
Quadrilateral QUAD is a rectangle. Find the value of x.
Angle 4 = 6x-16, angle 2 = 2x+4
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Answer by richard1234(7193) About Me  (Show Source):
You can put this solution on YOUR website!
It can be shown that angle 2 equals angle 3, since the diagonals of a rectangle are equal and the diagonals intersect at the diagonal. Also, the sum of two angles in a triangle equals the exterior angle of the third angle, so the measure of angle 2 plus the measure of angle 3 equals the measure of angle 4. Thus,

%282x%2B4%29+%2B+%282x%2B4%29+=+6x-16

4x+%2B+8+=+6x+-+16

2x+=+24 --> x+=+12