SOLUTION: How do I rewrite the equation -8x-5y=-45 as a function of x?

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Question 105783: How do I rewrite the equation -8x-5y=-45 as a function of x?
Found 2 solutions by bucky, Fombitz:
Answer by bucky(2189) About Me  (Show Source):
You can put this solution on YOUR website!
Given the equation:
.
-8x+-+5y+=+-45
.
To rewrite this equation as a function of x, begin by solving for y.
.
In this problem you need to get the term containing y on one side of the equation and everything
else on the other side. Start by getting rid of the term -8x on the left side. You can do
that by adding 8x to both sides. On the left side when 8x is added to - 8x, the two terms
cancel each other so the -8x disappears and you are left with:
.
-5y+=+8x+-+45
.
Now solve for y by dividing both sides by -5 which is the multiplier of the y term. This
division leads to:
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y+=+8x%2F%28-5%29+-+45%2F%28-5%29+=+-%288%2F5%29x+%2B+9+
.
Now just replace the y with f(x). This leads to the answer:
.
f%28x%29+=+-%288%2F5%29x+%2B+9
.
Hope this helps you to understand the problem a little better.
.

Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
You need to get to a form of the equation where y is on one side and everything else is on the other.
y=...
You get to use your properties to get there.
-8x-5y=-45
cross%28-8x%29%2Bcross%288x%29-5y=-45%2B8x Additive inverse of (-8x) of 8x to both sides.
-5y=-45%2B8x Simplify.
cross%28-5%29y%2Fcross%28-5%29=%28-45%2B8x%29%2F%28-5%29 Multiplicative inverse of (-5) or (-1/5) to both sides.
y=%28-45%2B8x%29%2F%28-5%29 Simplify left hand side.
y=-45%2F-5%2B8x%2F%28-5%29 Distributive property.
y=9-8x%2F5
Now it is in a form where y is a function of x.
y%28x%29=9-8x%2F5