Let this angle be x.

2(90-x)=0.5( 180-x)

180-2x=90-0.5x

180-90=-0.5x+2x

90= 1.5x

x=60

The second question:

relation of equality

Reason:

Angle 1+ angle 2= angle 3+ angle 2 = 180.

(according to the meaning of the question)

Angle 1= angle 3

The third question:

Let this angle be y.

90-( 180-y)=0.4y

90- 180+y=0.4y

-90 =-0.6 years

y= 150

The fourth question:

Let the smaller angle be d.

d+20+d=90

2d=90-20

2d=70

d=35

The fifth question:

(6x+8) +(4x-8) =90

6x+8+4x-8=90

10x=90

x=9

I hope it helps you! ! ! ! ! ! !