Solution to this equation?

Question

I understand factoring but i don't understand how the signs change.

-8+3(x-3)=-2

Answer 1

To solve this equation, you need to get x by itself, which basically means that you'll need to "undo" everything that has been done to tie up the x.

First, go ahead and factor in the 3 to get rid of the parentheses:
-8+3(x-3)=-2
-8 + 3x - 9 = -2 (note that the 9 is negative because we took a positive 3 times a negative 3 [since that's what "minus 3" really means], and positive times negative is negative. If you multiply 2 positives or 2 negatives, then the result is positive.)

Add the -8 and -9:
-17 + 3x = -2

I can switch the terms around on the LH side just to make it look prettier:
3x - 17 = -2

Now, to get x by itself, we first need to undo subtracting by 17. To do that, we're just going to add 17 to both sides:
3x - 17 + 17 = -2 + 17
3x = 15

Now x is being multiplied by 3 - we need to undo that, too. So divide both sides by 3:
(3x)/3 = 15/3
x = 5

Hope this helps with understanding how the signs change!

Answer 2

First: eliminate parenthesis - use distribution > multiply the outer term with the terms in the parenthesis...

- 8 + 3(x) - 3(3) = - 2

- 8 + 3x - 9 = - 2

Sec: combine "like" terms...

-17 + 3x = - 2

Third: add 17 to both sides...

-17 + 17 + 3x = - 2 + 17
3x = 15

*Solve for "x" by isolating it on one side - divide both side by 3...

3x/3 = 15/3
x = 5

Answer 3

x = 5 Here's how - -8+3x-9=-2 then -17 +3x=-2 Add 17 to both sides and you are left with 3x=15 divide both sides by 3 so x=5

Answer 4

-8 + 3(X-3) = -2

Combine like signs.

-8 + 3(X-3) = -2 + 8

(When a number passes over the equals sign the sign changes ex. positive to negative and vice versa)

3(X-3) = 6

Now multiply.

3X - 9 = 6


3X - 9 = 6
+9 +9
---------------------
3X = 15

Now divide.

3X = 15/3

X = 5

Answer 5

so let's just work with the factor...

3(x-3)

to factor that out you multiply 3 by EVERYTHING inside of the brackets, so

3*x and 3*(-3)

so you would get

(3x - 9)

Now that we have that factored out let's add the rest of the equation

-8 + (3x - 9) = -2

Time to isolate the x add 8 to both sides

3x-9=(-2 +8)

3x-9 = 6

Now add the 9

3x = 15

divide 3

x = 5

And you got it ;)

Answer 6

-8+3(x-3)=-2
-8+3x-9= -2 (distributive)
3x-17= -2 (combine like terms)
3x= 15 (add 17)
x= 5 (divided by 3)

Answer 7

-8+3(x-3)=-2
3(x-3) = 8-2
3x - 9 = 6
3x = 15
x = 5