Question

In a triangle, one angle is 3 times the first, another is 5 times the first. How large is the largest angle in degrees? round your answer to the nearest degree

Answer 1

let's recall that a triangle has a total of 180° for its interior angles.

x = first angle

3x = second angle, three times the first one

5x = third angle, five times the first one, and largest.

$\bf x+3x+5x=180\implies 9x=180\implies x = \cfrac{180}{9}\implies x = 20 \\\\\\ \stackrel{largest}{5(x)}\implies 5(20)\implies 100$