Question

How do you write `-4/9+2/9y=x` in standard form?

Answer 1

Our goal is to isolate Y.

First step: move the minus four ninths to the other side, so that you'll have:

(2/9)y = x + (4/9)

Note that as we pass an element adding from one side to the other, it goes from positive to negative and vice-versa for subtracting elements.

Second step: 2 is multiplying Y. We need to move it to the other side. As we change the operations to their inverse form (to preserve equality), this little boy number 2 goes to the other side dividing BOTH elements. Now, we'll have:

y/9 = x/2 + (4/18)

Note that as we divide 4/9 by 2, it becomes 4/18 because in the lower part of the fraction we'll have a multiplication: 9 times 2 = 18.

Third step: Now, we need to get the 9 that's dividing Y to the other side. Simple. On the other side, it will multiply BOTH elements, as follows:

y = (9x/2) + (36/18)

Or you can simplify the (36/18) dividing both upper and lower parts by 9, getting a new (4/2), which can be easily simplified to 2.

So:

y = (9x/2) + 2

If you want to be somewhat of a perfectionist, you can even divide 9 by 2 and stop to work with fractions. Like this:

Y = 4.5x + 2

Up to you, now: do you feel more comfortable with fractions or decimal numbers?

Cheers!