You need to know these two formulas:

For example,

Answer:
step number 1 is incorrect.
Step-by-step explanation:
Here is the solution of this equation [2x-31-1=2].
2x-31-1=2
or 2x-31=2+1
or 2x=2+1+31
or 2x= 34
or x=34/2
or x= 17
the answer of this equation is X=17.
Answer:
A, $1.08
Step-by-step explanation:
1.20 / 90 = 1.08
use a calculator
Answer: 4/7
Step-by-step explanation:
4/8 / 4/7
now you do multilpication so,
4x8
over
8x7
32/56 divided by 56/8=
4/7
hope i helped <33
One way to do this is use the fact that the exterior angles of all polygons add up to 360 degrees
So an exterior angle of a regular octagon = 360 / 8 = 45 degrees.
So each interior angle = 180 - 45 = 135 degrees
so total measure of all angles in octagon = 8 * 135 = 1080 degrees