Question

In a parallelogram ABCD,
a. Angle C = (3x + 15°), Angle D = (2x + 10º), find the value of x.
b. Angle A = 5y, Angle B = 3y + 20°, find the value of y.​ ​

Answer 1

Answer:

Angle a = Angle c ( opposite angles of a parallelogram are equal )

Similarly Angle b = Angle d ( opposite angles of a parallelogram are equal )

5y = 3x + 15° and 3y + 20 ° = 2x + 10 °

2x+10=3x+15

10-15=3x-2x

-5=x

X=-5

5y=3y+20°

5y-3y=20°

2y=20°

y=20°/2

y=10°

Answer 2

Answer:

a)AD//BC

So angleC+angle D =180°

(co interior angles. )

3x+15°+2x+10°=180°

5x=155°

x=31°

b)AB//BD

So angle A+Angle B=180°

(co interior angles. )

5y+3y+20°=180°

8y=160°

y=20°