Question

Given parallelogram ABCD, find x, y, length AB and Length BC.

Answer 1

x = 18, y = 5, AB = 23, BC = 8

Explanation:

The opposite sides of a parallelogram are equal, so

DC = AB , that is

2x - 13 = x + 5 ( subtract x from both sides )

x - 13 = 5 ( add 13 to both sides )

x = 18

and

BC = AD , that is

4y - 12 = 2y - 2 ( subtract 2y from both sides )

2y - 12 = - 2 ( add 12 to both sides )

2y = 10 ( divide both sides by 2 )

y = 5

Then

AB = x + 5 = 18 + 5 = 23

BC = 4y - 12 = 4(5) - 12 = 20 - 12 = 8

Answer 2

x = 18 y = 5

Explanation:

x + 5 = 2x - 13

x - 2x = -13 - 5

-x = -18

x = 18

2y - 2 = 4y - 12

2y - 4y = -12 + 2

-2y = -10|:(-2)

y = 5