How do you use the important points to sketch the graph of $y=x^2 - x - 12 = 0$ ?

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Answer 1 · 2017-07-26T17:50:09

Factorise first

If you factorise this equation, you will get:

$(x-4)(x+3)=0$

Putting each bracket equal to zero gives $x=4 or x=-3$ as your x intercepts (where the graph crosses the x axis).

If you put $x=0$ , this will give you your y intercept which in this case is $-12$ ( $0^2-0-12$ ).

As it's a quadratic (power of 2 in the equation) it will be a smooth, U-shaped curve going through the above points.

How do you use the important points to sketch the graph of y=x^2 - x - 12 = 0y=x^2 - x - 12 = 0?