Question

In a parallelogram ABCD ,if angle A=3x -20,angleB=y+15,angleC=x+40 than find the value of X&Y

Answer 1

x=30,y=105

in parallelogram opposite side are equal

3x-20 =x+40

3x-x= 40+20

2x = 60

x.=30

linear pair of angle are 180.

(3x-20)+(y+15)=180

3x +y =180+20-15

3*30 +y=195

y= 195-90

y = 105

Answer 2

Given: In a parallelogram ABCD, if angle A=3x -20, angle B=y+15, angle C=x+40.

To find: We have to find the value of x and y.

Solution:

To determine the value of x and y we have to follow the below steps-

A parallelogram has the opposite equal angles.

So, angle A=angle C.

Thus we can write-

$3x - 20 = x + 40 \\ 2x = 60 \\ x = 30$

The value of x is 30.

Again we know that in the case of a parallelogram the sum of linear angles are 180°.

So, we can write-

Angel A+ angle B=180°

$3x - 20 + y + 15 = 180 \\ 3 \times 30 - 20 + y + 15 = 180 \\90 - 20 + y + 15 = 180 \\ y = 180 - 85 \\ y = 95$

The value of x is 30 and y is 95.