# [SOLVED] Straight line graph

• Oct 17th 2008, 12:54 AM
helloying
[SOLVED] Straight line graph
It is known that x and y are related by the eqn of the form y=x²-ax+b where a and b are constant. Express this eqn in a form suitable for plotting a straight line graph.I am suppose to plot the graph to find value of a and b. I dont know what shld I plot against to get a straight line graph
• Oct 20th 2008, 05:44 AM
Ting
Quote:

Originally Posted by helloying
It is known that x and y are related by the eqn of the form y=x²-ax+b where a and b are constant. Express this eqn in a form suitable for plotting a straight line graph.I am suppose to plot the graph to find value of a and b. I dont know what shld I plot against to get a straight line graph

Hello

Probably too late, but here is one way.

$y-x^2 = -ax + b$

Subtract $x^2$ from the corresponding values of y, then plot these against x. Find the gradient (a) and the y intercept (b) of the line.

I know that might not be very clear. If you have the values of x and y, then I'll show you. There are a number of other ways to find the values of a and b too.

Hope that helps.