Graph

[Chikis]

Hello folks, here is a problem. I don't know how and where to start solving it:
A student is told to draw a linear graph on the same axis such that the intersection of the two graph will give the solutions to the equation x2+ 4x -7 =0. What is the equation of the linear graph he needs to draw?
A. x=1 B. x=-1 C. y=1 D. y=-1 E. x+y=1
I don't know where to start from. Can anyone help? Just give me hints that I will follow in proceeding towards the calculation. Please note that I mean x squared when I wrote x2. Thank you.

[shyamjayakannan]

find the two roots of the quadratic[[tex](x_1,0),(x_2,0)[/tex]] and then find the equation of the line passing through the two points