When 3 is added 5 times to a number the result is 15 if the number is 0, otherwise this is not true. However, the amount added to the number is always 15. Let's say the variable x is our number and y is the result, then x+3+3+3+3+3=y. You can add all the 3's together now. So you have x+15=y. Now if the starting number is 0, you have 15=y, so the result is 15.
If: 6x+8 = 32 Then: x = 4
25
4
36
4x2 - x = 3
If: 6x+8 = 32 Then: x = 4
4 times a number added to 7 times the number equals 33
4
The number is 3
25
18 is a solution to the equation 4 plus 7 times a number where the result is 9 times that number.
The number is 20.
9
4
169
x = -.25
36