Question

Find the measure of A:
A
15x
31x-2

Answer 1

30

Explanation:

Triangles add up to 180.

Your known sides are: 15x, 31x-2, and 90 (the square on the corner of the angle tells you that it's a right angle or 90 degrees.)

First make an equation to find X

this looks like: 15x+31x-2+90=180

I just added the sides we know and set them to equal 180. Because triangles add up to 180.

Now solve this by first combining like terms

15x+31x-2+90=180 (do the numbers with x's) so 15x+31x

46x-2+90=180 (now combine the numbers without X's) so -2+90

46x+88=180 (now since 88 is positive, do the opposite and subtract it from 180. This is because 180 is on the other side of the = sign.)

46x=92 (now since 46x means 46 times x, you do the opposite of multiplication and divide 92 by 46.

This gives you x=2

Now the last thing you need to do is solve for angle A

Angle A says "15x" so you can substitute our x value (2) for the x

This looks like 15(2) 15 times 2 is 30

so 30 should be your answer