calculus
posted by Kim on .
Hi, I have online homework for calculus and I have to input two equations that will describe this graph. I have an image but Jiskha won't let me link to any websites... if this is allowed the URL to the image of the graph is
img145.imageshack.us/ img145/1787/80193630 .png
without the spaces.
f(x)= _______ for x in the interval [ ___ to ___]
f(x)= _______ for x in the interval [ ___ to ___]
Personally, I tried
f(x)= 3/2x+2 for [2,2]
f(x)= 3x for [2,4]
The intervals are correct but the equations are not. Can someone help me with this?

Oops, for the interval of the first one it's [5,2]. Typo.

I was able to see your diagram.
Your slope for the first one is incorrect
(2,5) to ((5,5) has slope 10/7 = 10/7
so y = (10/7)x + b
for (2,5)
5 = 20/7 + b
35 = 20 + 7b
b = 15/7
equation : y = (10/7)x + 15/7
the second equation:
slope is correct
so y = 3x + b
using (2,5)
5 = 6 + b
b = 11
equation: y = 3x + 11 
Thank you very much. I think somewhere between wrong slopes and a mixup in the pointslope form equation, I messed up the equations. But I got it now. Thanks a lot!