Temperature coefficient of resistance problem

[sphys4]

Homework Statement

For the resistance versus temperature graph below, find (a) the resistance at T = 20°C and (b) the temperature coefficient of resistance alpha .

http://tinypic.com/r/jhufkn/7

I don't know if the graph is showing up or not, it isn't for me... so here's the link.
http://tinypic.com/r/jhufkn/7

The Attempt at a Solution

I believe that this is the formula i am supposed to use, but i feel like i don't have enough numbers or data to plug in. R(T) = R(To) ( 1 + alpha (T-To) )

 

[rl.bhat]

You can use the formula
α = (R2 - R1)/(R1t2 - R2t1)
From the graph, you can see that at 20 degree C R1 = 5.1 ohm and at 30 degree C R2 = 5.2 ohm. find α.
Interpolate the graph towards the axis. You can find R(0). Then use the formula which you have mentioned to find R(20)