Let p(x) be a linear function such that p(−2) = 0 and p(1) = 3. (a) Graph the function p(x) labelling the important points. Note. You will be using the same axe

Question

Let p(x) be a linear function such that p(−2) = 0 and p(1) = 3. (a) Graph the function p(x) labelling the important points. Note. You will be using the same axes to graph another function in the next problem, so read that problem before graphing p(x). (b) Determine a formula for p(x).

Answer 1

Let p(x)=ax+b

 

p(-2)=0=a*(-2)+b
p(1)=3=a*1+b            Substract the first equation from the second

        3=a+2a=3a, so a=1.

        Since a=1, plug into one of the equations above to find b:  I chose the second:3=1* 1+b so b is 2, thus p(x)=x+2