Question 89117
{{{y=x^2+2x-15}}}
The x intercepts are the points where y=0. So set y equal to zero in the equation and solve for x:
{{{0=x^2+2x-15}}}
Factor this to get your values of x:
{{{x^2+2x-15=0}}}
{{{(x+5)(x-3)=0}}}
So now you have 2 factors, (x+5) and (x-3). Since their product is equal to zero, each individual factor can be equated to zero. Then, it is easy to solve for x:
{{{x+5=0}}}
{{{highlight(x=-5)}}}
{{{x-3=0}}}
{{{highlight(x=3)}}}
Good Luck,
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