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Describe how factoring can help you find the x intercept of a graph

User SHiRKiT
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1 Answer

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If we factor an expression (such as quadratic/cubic), we will have a factored form with some expressions in parenthesis.

To find x-intercepts (x-axis cutting point), we set each of these factors equal to 0 and find the corresponding x value. That is hte x-intercept.

As an example, let's find the x intercepts of the parabola


y=x^2-5x+6

x intercept is the x-cutting point. We find this by setting y to 0. Thus,


x^2-5x+6=0

Now, we have to factor the quadratic to find the x intercepts, thus:


(x-2)(x-3)=0

Thus, as said earlier, we set each expression [in parenthesis] equal to 0 and find the corresponding x-value.

Thus,

x - 2 = 0

x = 2

and

x - 3 = 0

x = 3

The x-intercepts are x = 2 and x = 3

User Maurdekye
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