AzizHusain

Distribute the 3:

9 - ((3*-4) + 3*3x) + 12x

Multiplying it out:

9 - (-12 + 9x) + 12x

Distribute the negative:

9 + 12 - 9x + 12x

Combine like terms:

3x + 21.

Distribute the -5 and 5 and combine like terms:

(-5*1 - (-5*5x)) + ((5*-8x) - 5*2) = -12x

Multiplying all of it out:

-5 - (-25x) - 40x - 10 = -12x

Combine like terms and keep track of negatives:

-5 + 25x - 40x - 10 = -12x

-15 - 15x = -12x

Add 15x to both sides:

-15 = 3x

Divide both sides by 3:

-15/3 = x.

x = -15/3

x = -5.

a times a = a*a = a².

7n - 2 = 6n - 2n

First, let's collect like terms on the right-hand-side:

7n - 2 = 4n.

Now, we can subtract 7n from both sides:

-2 = 4n - 7n

-2 = -3n.

Finally, we divide both sides by -3:

-2/-3 = n.

n = 2/3.

Please post questions you have about physics.

First, it is easiest to get rid of the 1/3 by multiplying both sides by 3:

3m = bc.

Now, all you have to do is divide both sides by b:

3m/b = c.

c = 3m/b.

The " - " key located next to "0" on the top of a keyboard. 

OR

The " - " key located under "X" on the calculator located on the home page. 

What equation? Need the equation to help you.

If you are dividing a number or fraction by a fraction, then you use the skip, change, & flip method where you multiply by the reciprocal: 3 divided by 4/3 = 3 * 3/4 = 9/4.

If you have 1/4 + 1/4, then you just directly add.