how do you find y in a equation?
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Otis
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Hello itr2206. The short answer to your question is, "It depends on the equation." There are different types of equations containing y, in pre-algebra. For example, y could be the only symbol, or there could be additional symbols. Maybe y appears in denominator and/or numerator positions.
Are you asking about very simple equations, like this:
5·y = 15/2
If not, then please post an example equation. If you have a specific exercise, please include all given information and instructions. Thanks!
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Otis
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That's possible, in some exercises, but we'd need more information before we could find a particular number for x. Without more information, x could be any Real number. Here are some example (x,y) pairs that satisfy the equation y=2x-6.
(3, 0) \(\;\) (22003, 44000) \(\;\) (5/2, -1) \(\;\) (3.9, 1.8)
I don't know whether you've learned about graphing points, but those types of exercises might ask us to find y for some values of x, and we get to pick the numbers. We calculate the y-value for each x we choose. Let's choose x=3. In the equation, we replace symbol x with the number 3 and write:
y = 2(3) - 6
After substituting 3 for symbol x, we do the arithmetic (using the Order of Operations).
y = 6 - 6
y = 0
The (x, y) pair is (3, 0) and it's just one solution for the equation. If we calculate many (x,y) pairs and draw the points, they form a straight line.
In other exercises, we might need to pick a number for y first, and then find x. Or maybe we're given a specific number for y (like 44000) and we then solve 44000=2x-6 for x. There are many different things we can do with the equation y=2x-6.
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HallsofIvy
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Perhaps you don't understand what "find y" means! If you were given a value of x and asked to find the value of y corresponding to that value of x, then, yes, you would "use that to find y". But, in general, "find y" just means to reduce whatever formula you are given to the form "y= " where the right side is either a number or a formula that doesn't involve x. In this example, "y= 2x- 6", the formula is already of that kind. So unless you are given specific values of x, there is nothing more to be done.