Write the equation 5x + 4y = 10 so that y is a function of x.
You must show work in order to receive full credit.
A. y= 5/4x + 2.5
B. y= 1.2x - 5/2
C. y= -5/4 - 5/2
D. y= -5/4x + 5/2

Question

Write the equation 5x + 4y = 10 so that y is a function of x. 
You must show work in order to receive full credit.
A. y= 5/4x + 2.5
B. y= 1.2x - 5/2
C. y= -5/4 - 5/2
D. y= -5/4x + 5/2

anonymous · Answer

The question is essentially asking you to convert the equation, which is in standard (ax + by = c) form, into slope intercept form (y = mx + b; m being the slope and b being the y intercept).
The slope of an equation in standard form is -a/b. In this case it would be -5/4. The y intercept of an equation in standard form is c/b. In this case it would be 10 / 5 = 2.
The other way to do it (i.e. how that shortcut was derived) is through algebra. Isolate y on the left side of the equation by subtracting 5x from both sides and then dividing both sides by four.

anonymous · Answer

So does (x)  equal 2 ?

anonymous · Answer

The question isn't asking you to solve for x. However, if you were to isolate x on the left side, x = 2 - (4/5)y is the answer, not x = 2.