Question 55958
graph f(x)=-2x + 2
Assuming you are using normal vertical 'y' and horizontal 'x' graphing paper:
Remember f(x) = y:
y = 2x + 2
Choose some values of x and find y using the above equation:
1st value as an example; x = -2: 
y = 2(-2) + 2: 
y = -4 + 2: 
y = -2
:
 x | y
-------
-2 |-2
-1 | 0
 0 | 2
 1 | 4
Plot these x,y coordinates and draw the line.   
:
rewrite the equation -x - 10y = 50 as a function of x
- x - 10y = 50
    - 10y = +x + 50
        y = x/-10 + 50/-10
        y = -.1x - 5
You can also write it: f(x) = -.1x - 5
: 
given f(x) = 4x - 5, find f(a-1): Substitute (a-1) for x
f(a-1) = 4(a-1) - 5
f(a-1) = 4a - 4 - 5
f(a-1) = 4a - 9
: 
given f(x)= 5x^2 - 3x + 1 find f(-2):Substitute (-2) for x
f(-2) = 5(-2)^2 - 3(-2) + 1
f(-2) = 5(4) - (-6) + 1
f(-2) = 20 + 6 + 1
f(-2) = 27