Question

Vertex angle A of isosceles triangle ABC measures 20 degrees more than three times angle B. What is angle C?

Answer 1

`angleC=32^@`

Explanation:

`angleB " and "angleC" are the equal base angles"`

`"let the measure of "angleB=x`

`"then "angleA=3x+20`

`rArr3x+20+2x=180`

`rArr5x+20=180`

`rArr5x=180-20=160`

`rArrx=160/5=32`

`rArrB=C=x=32^@`

`rArrA=3x+20=(3xx32)+20=116^@`