The sum of the measures of two angles is 180°. one angle measures 3a and the other angle measures 2a - 25 find a. then find the measure of each angle.

A should be here

So first make an equation

180 = 3a + 2a - 25
combine like terms
180 = 5a - 25
add 25 to both sides
205 = 5a
divide both sides by 5
41 = a

now substitute 41 into the two angles
3(41) = 123
2(41) - 25 = 82 - 25 = 57

so one angle is 123 degrees
the other angle is 57 degrees

to check it, just add 123 + 57 = 180
yep! its correct

i hope this helps!!