Question 244895
graph the points and see what they look like.


if they look like a straight line, then your equation will be of the form:


ax + by = c

or:


y = mx + b


if they look like a parabola (shaped like a u or an upside down u), then your equation will be of the form:


ax^2 + bx + c = 0


or:


(x-h)^2 + k = 0


the equation depends on the shape of the graph.  


that's a starting point.


from there you work back.


with a quadratic equation, you find the 0 points and solve backwards.


example:


when y = 0, x = 3 and x = -2


you have x = 3 and x = -2 which leads to the equation (x-3) * (x+3) = 0


you multiply those factors together and you have the quadratic equation.


this is exactly the reverse of how your would solve the quadratic equation to get the roots in the first place.


if you're still having trouble, send me the points and i'll take a look at it.