A, B and C lie on a straight line. Given that angle

y

= 128° and angle

z

= 91°, work out

x

.

x = 37°

Step-by-step explanation:

The exterior angle of a triangle is equal to the sum of the 2 opposite interior angles .

y is an exterior angle of the triangle , then

y = x + z , that is

128° = x + 91° ( subtract 91° from both sides )

37° = x

x+91+(180-y)=180

180-128=52

x+91+52=180

143+x=180

x=37

Hope This Helps!!!

can i see the following ?

step-by-step explanation: