Question

Find the sizes of the angles of a parallelogram if one angle is 20° less than twice the smallest angle.

Answer 1

Let smallest angle be x°
then the other will be (2x-20)°
we know that adjacent angles of ||gm are supplementary
therefore,
x + 2x-20=180
3x=180+20
3x=200
x=200/3
x=66.6°
other angle =2× 66.6. -20= 113.3°

Answer 2

let smallest angle be x°

then the other will be (2x-20)°

we know that adjacent angles of ||gm are supplementary

therefore,

x + 2x-20=180

3x=180+20

3x=200

x=200/3

x=66.6°

other angle =2× 66.6. -20= 113.3°