# Thread: 3rd time I need help on this! :(

1. ## 3rd time I need help on this! :(

I still don't understand these. Can someone help me on these equations? And show me how to do them step by step so I can do them on my own in the future?

$\displaystyle 3x-1/ 4=-5/11$

$\displaystyle 3x/4 +2=4x-1$

and this

Complete the table, and write a rule relating x and y (write an equation)

2. Originally Posted by peachgal
I still don't understand these. Can someone help me on these equations? And show me how to do them step by step so I can do them on my own in the future?

$\displaystyle 3x-1/ 4=-5/11$
First, you could clear the fractions by multiplying by 4 and 11, or 44.

$\displaystyle 132x - 11 = -20$

Next, get x by itself, adding 11 to both sides, and then dividing by 132...

$\displaystyle 132x = -9$

$\displaystyle x = -\frac{9}{132}$

Remember, you can add or subtract the same value to both sides of the equation, and it stays equal. Not just numbers, but variables too, like x, or 5x, etc. And you can multiply or divide every term on both sides of the equation by the same value. Again, number and variables work.
$\displaystyle 3x/4 +2=4x-1$
Try it on this one.
1. Clear the fraction by multiplying.
2. Get the x terms on one side, and the numbers on the other, by adding and subtracting as needed.
3. Get x by itself by dividing.

and this

Complete the table, and write a rule relating x and y (write an equation)

Well, the rule or equation will be linear, and so should be of the form:

$\displaystyle y = mx + b$

You need to figure out m and b. Use the entries where both x and y are given (there are four of them) to do this. If you pick the right one, you should be able to get a value for b. Then, use one of the other three to find m.

You'll need to use the techniques from the first two problems when solving for b and m.

-Scott