## Need help with this function problem please!

Quadratic equations and inequalities, variation equations, function notation, systems of equations, etc.

### Need help with this function problem please!

Could someone show me how to solve this? Hope I write this correctly. the -5/2x and the 5/6x are fractions.

Find the input value for which the functions f(x)= -5/2x+2 and g(x)= 5/6x-4 have the same output value.
zellm

Posts: 2
Joined: Wed Apr 29, 2009 9:13 pm

zellm wrote:Find the input value for which the functions f(x)= -5/2x+2 and g(x)= 5/6x-4 have the same output value.

If the function values are the same for some value of x, then set the function expressions equal and solve for that value of x.

Your formatting is ambiguous, so I can't present the equation, since I can't tell what the functions are. Sorry!

stapel_eliz

Posts: 1706
Joined: Mon Dec 08, 2008 4:22 pm

### Re: Need help with this function problem please!

Does this help any? This is a sample question for an exam.

Find the input value for which the functions f(x)= (-5/2)x+2 and g(x)= (5/6)x-4 have the same output value.
zellm

Posts: 2
Joined: Wed Apr 29, 2009 9:13 pm

zellm wrote:Does this help any?

Find the input value for which the functions f(x)= (-5/2)x+2 and g(x)= (5/6)x-4 have the same output value.

Ah. That would not have been what I would have guessed you'd meant. Thank you; that is helpful!

To find the input value "x" that makes the output expressions "-(5/2)x + 2" and "(5/6)x - 4" equal to each other, follow the instructions provided earlier: Set the output expression equal to each other:

. . . . .-(5/2)x + 2 = (5/6)x - 4

...and solve the linear equation for x!

A good first step might be to multiply through by 6, thus getting rid of the denominators.

. . . . .-15x + 12 = 5x - 24

...etc, etc, and so forth.

stapel_eliz

Posts: 1706
Joined: Mon Dec 08, 2008 4:22 pm