Respuesta :

Answer:

7.  x = 5

8. x = 2, y = 6

9. x = 21, y = 39

Step-by-step explanation:

For a parallelogram, the lengths across intersection are equal.

7. For a parallelogram, the lengths across intersection are equal.

So that,

3x = 4x - 5

4x - 3x = 5

 x = 5

8. For a parallelogram, the lengths across intersection are equal.

So that,

2x = 4

x = [tex]\frac{4}{2}[/tex]

x = 2

and

y - 1 = 2y -7

7 - 1 = 2y - y

y = 6

x = 2, y = 6

9. For a parallelogram, opposite angles have equal value.

Thus,

3x = (4x - 21)

3x = 4x - 21

x = 21

and

3y = (y + 78)

3y = y + 78

3y - y = 78

2y = 78

y = [tex]\frac{78}{2}[/tex]

  = 39

y = 39

x = 21, y = 39