Question 394516
let angle 1 be {{{x}}}
let angle 2 be {{{x + 10}}}
let angle 3 be {{{(x+10) - 30}}} 
when you add up all angles in a triangle, they equal 180
so your equation would be
{{{x + x + 10 + 2(10 + x) - 30}}}
combine like terms and you get 
{{{4x = 180}}}
{{{x = 45}}}
so angle 2 would be {{{10 + 45 = 55}}}
and the last angle would be {{{180 - 55 - 45 = 80}}}
the solution is
angle 1 = 45
angle 2 = 55
angle 3 = 80