Question

find the value of b in given figure.

Answer 1

Given,

The measure of four angles 50, 35, b-20, 10.

To Find,

The value of b.

Solution,

We can use the property of angles on a straight line to get the value of b.

Now,

50+35+b-20+10 = 180

b + 75 = 180

b = 105

Hence, the value of b is 105.

Answer 2

We need to recall the angle of a straight line.

The angle of a straight line is $180$°

If one or more lines cut a straight line at any angle, the sum of all these angles must add up to $180$°.

Adding the given angles,

$50+35+(b-20)+10=180\\95+b-20=180\\75+b=180\\b=180-75\\b=105$

Hence the value of $b=105$°