Triangle= 180 degrees
Angle = 37.5 degrees
Supplement angle = 105 degrees
If you multiply the angle (37.5) by 2 and then add 30, it gives you 105. Then add 37.5 twice to make up the other two angles of the triangle and it gives you 180 total degrees as a triangle should.
It could be PEMDAS.
That means solve by this order:
1). Parenthesis
2). Exponents
3). Multiplication
4). Division
5). Addition
6). Subtraction
To remember the order they say it like
this " Please Excuse My Dear Aunt Sally "
Step-by-step explanation:
if we add 18 to both side then it becomes 5x=10x+15 and if we divide by five, x=2x+3