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Cheese2
Feb 10, 2009, 09:02 PM
How do you solve a function if it is something like this:

Suppose f(x)= (-9)x + 2 and g(x)= (-3)x + 3. Find each value.

Then trying to solve for something like this:

1.) 3g(4)
2.) g(-2)/f(3)

How do you suppose I should solve these?

NOTE: THESE ARE MADE UP FROM ME. I NEED HELP WITH SIMILAR ONES.

rwinterton
Feb 11, 2009, 09:49 AM
I might be missing your question, but here's what I think the answer is (if I understood your question correctly).

Think of a function as a line (usually curved in some way) across a piece of graph paper. You can graph the line by entering a value for "x". For example,

f(x) = (-9)x + 2
f(1) = (-9)1 + 2 = -7
f(2) = (-9)2 + 2 = -16
f(3) = (-9)3 + 2 = -25

Of course, x can take on any value including fractional values. If you put graph the result ( f(x) ) on the "y" axis and "x" on the "x" axis, you'll see the line.

Now, if you have two lines, f(x) and g(x), you can graph both of them and the *solution* is the point where they intersect. You can also take the equations of the curves and solve them directly for the intersection. Replace f(x) and g(x) with "y"

y = -9x + 2
y = -3x + 3

note that these are equations for a lines (not curves) and these lines are parallel (they do not intersect) so there is no "solution".

Cheese2
Feb 12, 2009, 07:15 AM
I might be missing your question, but here's what I think the answer is (if I understood your question correctly).

Think of a function as a line (usually curved in some way) across a piece of graph paper. You can graph the line by entering a value for "x". For example,

f(x) = (-9)x + 2
f(1) = (-9)1 + 2 = -7
f(2) = (-9)2 + 2 = -16
f(3) = (-9)3 + 2 = -25

Of course, x can take on any value including fractional values. If you put graph the result ( f(x) ) on the "y" axis and "x" on the "x" axis, you'll see the line.

Now, if you have two lines, f(x) and g(x), you can graph both of them and the *solution* is the point where they intersect. You can also take the equations of the curves and solve them directly for the intersection. Replace f(x) and g(x) with "y"

y = -9x + 2
y = -3x + 3

note that these are equations for a lines (not curves) and these lines are parallel (they do not intersect) so there is no "solution".

Thank you very much. I understand now.