Question

Examine triangle ABC.

Triangle A B C. Angle B is 79 degrees. Exterior angle to A is (x + 5) degrees and the exterior angle to C is x degrees. What is the value of x?

37

48

127

138

Answer 1

c127

Explanation:

Answer 2

x=127

Explanation:

total sum of all angle of triangle is 180 degree

Now,

taking angle A let interior angle be Y

taking angle C let interior angle be Z

Again, In angle A

the sum of interior angle and exterior angle is 180 degree being staright line

Or, y+(x+5)=180

or,x+y=180-5

or, x+y=175

or,y=175-x --------eqn 1

In angle C

the sum of interior angle and exterior angle is 180 degree being staright line

or, x+z=180

or, z=180-x ----------eqn2

Again, In triangle ABC

total sum of all angle of triangle is 180 degree.

Angle A+ Angle B + AngleC=180

Or, y+79+z=180 -------eqn3

putting the value of eqn-1 and eqn-2 in eqn-3

Or, 175-x+79+180-x=180

Or, 431-180= 2x

Or, 254÷2=x

hence X= 127 degree