Answer:
72°
Step-by-step explanation:
So the three angles of a triangle always add up to 180°. This means that
[tex]15x + 21x + 24x = 180[/tex]
This becomes:
[tex]60x = 180[/tex]
And solves as:
[tex]x = 3[/tex]
The largest angle has to be the one marked with 24x because it has the largest coefficient and x is a constant.
[tex]24x = 24(3) = 72[/tex]
The measure of the largest angle in the triangle is 72°.
