Question

Find the measure of each angle in triangle abc.

Answer 1

recall that the sum of all interior angles in a triangle is 180°.

therefore, a + b + c = 180°

$\bf (\stackrel{a}{50-x})+(\stackrel{b}{9x-40})+\stackrel{c}{90}=180\implies 8x+100=180 \\\\\\ 8x=80\implies x=\cfrac{80}{8}\implies x=10\\\\ -------------------------------\\\\ (\stackrel{\stackrel{a}{50-x}}{50-10})=40\qquad \qquad \qquad \qquad \stackrel{\stackrel{b}{9x-40}}{9(10)-40}=50$