How many times does X squared minus 4X -12 cross the X axis

Mathematics

1 answer:

kolbaska11 [484]3 years ago

4 0

We can solve this problem using discriminant.

x^2-4x-12's discriminant is

(-4)^2-4*-12=16+48 which is clearly larger than 0

This means that it crosses over the axes 2 times.

In case you don't know what discriminant is, its in equation ax^2+bx+c

the discriminant is b^2-4ac.

If its positive it has 2 crosses with x axis, if negative then 0 crosses, if 0 then 1 cross.

Hope this helped at least a little bit :D

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<em><u>Hope this helps.</u></em>

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