Question

in triangle ABC, angle a= x + 30 degree , angle b=3x-30 , angle c= 4x-60 degree . Is it a equilateral triangle or no and prove it

Answer 1

x+30+3x-30+4x-60=180
8x=240
x=30 thus,A=60,B=60&C=60

Answer 2

(x+30)°+(3x-30)°+(4x-60)°=180°

8x-60°= 180°

8x = 180°+60°

8x = 240°

x = 240°÷8

x =30°

First angle =30°+30°

=60°

Second angle =(3 × 30)° - 30°

=60°

Third angle = (4 × 30) - 60°

= 120° - 60°

= 60°

Yes,it is equadrilateral angle.