Finding equation of a Tangent Line

Find an equation of the line that is tangent to the graph of *f* and parallel to the given line.

*Function*: *f*(*x*) = 2*x^*2

*Line*: 4*x* – *y* + 4 = 0

Tell me what I'm doing wrong. According to my instructor's directions:

**Step 1. Find the slope of the tangent line:**

http://www.sitmo.com/gg/latex/latex2...%5E2%7D%7Bh%7D

Do the algebra, reduces to *4x-2h* - the limit/slope is 4x.

Step 2. Find the slope of the given line:

*4x – **y + 4 = 0* same as *y=4x+4 *and so *m=4*

**Step 3. Set the slope of the tangent equal to the slope of the given line, and solve for x. **

*4x=4 so x=1*

**Step 4. Use the values from above to find the equation of the line.**

(So elsewhere in the lecture, he mentions that if x=1, then your reference point is (1,1) - if someone else can explain why, I'd appreciate that too. I'm not getting that. But assuming that it is....)

y-1=4(x-1)

y-1=4x-4

y=4x-3

Why isn't this right? What am I missing? I'm sure it's something obvious and dumb?