if 5x-10=25 what is the value of x-2 ?

Why not just divide every term by 5?  The answer is immediate:  x-2 = 5

Let x - 2  = the answer

then x = the answer + 2

Therefore

5(the answer + 2) - 10 = 25    Add 10 to both sides

5(answer + 2) = 35                Distribute 5 over the terms in the parentheses on the left side

5*answer + 10 = 35                 Subtract 10 from both sides

5*answer = 25                          Divide by 5 on both sides

answer = 5

And that's the "answer' for x - 2

In order to answer the question, you have to first find the value of x in the first equation. Once you find x, you plug that value into the second equation. When finding the value of x, you have to do the opposite of the current operation applied to the number/variable (in this case just number) to get x by itself. If you do the operation to one side of the equation, you have to do it to the other as well. The opposite of addition is subtraction which means that the opposite of subtraction is addition, and the opposite of multiplication is division which means that the opposite of division is multiplication. For this equation:

5x-10=25

The opposite of subtraction is addition, remember? We need to add 10 to both sides of the equation to keep it balanced.

5x-10+10=25+10

Solve

5x=35

The opposite of multiplication is division, so we need to divide both sides by 5.

5x÷5=35÷5

Solve

x=7

Since x=7, substitute it back into the original equation.

x-2 becomes 7-2.

7-2=5

 Questions?