90+x+13+x+23=180

Question

using the triangle sum theorem, how would combine the two x's?

Answer 1

By adding them.

2x+90+13+23=180

2x+126=180

2x+126 = 180

-126 -126

2x=54

2x/2 = 54/2

x=27

Answer 2

I am going to assuming your 3 angles are:

90

x + 13

x + 23

Just add up the left side/simplify just like you would any algebra problem

(90) + (x +13) + (x + 23) = 180

2x + 126 = 180

2x = 54

x = 27

So your 3 angles are

90

(27) + 13 = 40

(27) + 23) = 50

Double check that every adds up to 90?

90 + 40 + 50 = 90

90 = 90  good

Answer 3

90+x+13+x+23=180

Rearrange it to make it easier to look at. All x's first, then numbers.

x + x + 90 + 13 + 23 = 180

one x plus one x equals to two x's

2x + 90 + 13 + 23  = 180

Add the numbers on the left side

2x+ 126 = 180

Subtract 126 on both sides

2x +126 - 126 = 180 -126

2x = 54

Dividing both sides by 2

x = 54/2

x = 27