Question

Find the value of x for which ABCD must be a parallelogram.

Answer 1

D. X = 8 , Y = 6
3x - 14 = x + 23x - x = 2 + 142x = 162x / 2 = 16/2x = 8
To check: 3x - 14 = x + 2 ;  3(8) - 14 = 8 + 2  ;  24 - 14 = 10  ; 10 = 10
4y - 7 = y + 114y - y = 11 + 73y = 183y / 3 = 18 / 3y = 6
To check: 4y - 7 = y + 11 ; 4(6) - 7 = 6 + 11  ;  24 - 7 = 17  ; 17 = 17
hopes it helps:)

Answer 2

If those are angles then they must be equal as one of the conditions of a parallelogram.
5x - 1 = 2x + 5 Add 1 to both sides
5x = 2x + 5 + 1
5x = 2x + 6 Subtract 2x from both sides.
5x - 2x = 6
3x = 6 Divide by 3
x = 6/3
x = 2

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