First of all, it helps to know how to add and subtract integers. Otherwise, it's like trying to swim with one hand tied behind your back.

The basic strategy of all this is to get x by itself without any negative sign in front. Remember that -x means (-1)x.

The first I do is get rid of the brackets. For example, if I have something like x + (-2) = 6, I simplify it to x - 2 = 6. It makes my life a lot easier. You should know how to do this for both adding and subtracting.

The other thing to remember is that **x is a number**. That means
you can add or subtract it just like any other number.

OK, enough talk. Let's do a couple of examples.

**Example 1:** Solve

-8 - x = 6

Because we are subtracting x on the left hand side, (remember we want a positive x) we add x to both sides:

-8 - x + x= 6 + x

-8 = 6 + x

Of course, -8 - x + x = -8 + 0 = -8

Now we want x by itself. So, we subtract 6 from both sides.

-8 = 6 + x

-8 - 6 = 6 + x - 6

-14 = x

So, our answer is -14.

**Example 2:** Solve

-x + (-3) = 6

The first thing I do is get rid of the brackets.

-x - 3 = 6

Now we can follow the same strategy as the last problem.

-x - 3 = 6

-x - 3 + x = 6 + x

-3 = 6 + x

-3 - 6 = 6 + x - 6

-9 = x

Our answer is -9.

Basic add/subtract solve for x

Basic multiply/divide solve for x

Basic add/multiply mixtures

Solving basic problems involving brackets

What is cross-multiplying?

What is the quadratic formula?

Strategy for solving quadratic problems

Solving quadratic problems involving brackets

Solving quadratic problems involving fractions

Basic multiply/divide solve for x

Basic add/multiply mixtures

Solving basic problems involving brackets

What is cross-multiplying?

What is the quadratic formula?

Strategy for solving quadratic problems

Solving quadratic problems involving brackets

Solving quadratic problems involving fractions

Copyright © 2011 - Mathwizz.com all rights reserved