Question 425871
sandard form of a quadratic equation is:

ax^2 + bx + c = 0


a is the coefficient of the x^2 term
b is the coefficient of the x term
c is the constant term


a,b,c are use in he equation x = (-bą√(b^2-4ac)2a


you replace a,b,c in the equation with the value you derived from the standard form of your equation.


that provides you with the x value of when the graph of the equation crosses the x axis.


an example


your equation is x^2 + 3x - 10 = 0


this equation is already in standard form of ax^2 + bx + c = 0


this gives you:


a = 1
b = 3
c = -10


plug those values into your quadratic equation and you get:


x = {{{((-3) +- sqrt((-3)^2 - (4*1*(-10))))/(2*1)}}}


simplify this equation to get:


x = {{{((-3) +- 7)/2}}}


solve for x to get:


x = -5 or x = +2


those are the roots of your equation.


a graph of your equation looks like this:


{{{graph(600,600,-10,10,-15,15,x^2 + 3x - 10)}}}


you can see that the graph crosses the x-axis at x = -5 and at x = 2