Question

Prove that the sum of three angles of a triangle is 180º. Using this result, find the value of x
and all three angles of triangle, if the angles are (2x + 7), (2x - 25) and (3x-12)

Answer 1

Answer:

for the first part u will use exterior angle property .i.e. The sum of two interior angles is equal to the exterior angle and the linear  pair property.

for the next part

2x+7+2x-25+3x-12=180

7x-30=180

7x=210

x=30

Step-by-step explanation: