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What’s the smallest zero for the function h(x)=4x^2-8x-60

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Answer:

-3

Explanation:

In order to find the smallest zero, we will have to find out all the zeros of the function.

In case you are wondering what a zero is, it is the x-value or the domain intersections. The points where the parabola intersects the x-axis.

4x² - 8x - 60 = 0

Why zero?

We know that the parabola intersects the x-axis and when it does, the y-value is 0. h(x) is nothing but 'y'.

4(x²-2x-15) = 0 → I took the gcd as 4 and did it accordingly.

x² - 2x - 15 = 0 → Divide on both sides with 4

Now, what multiples to -15 but adds up to -2?

-5 and 3

x² + 3x - 5x - 15 → Grouping the terms

x ( x + 3 ) - 5 ( x + 3 ) → Taking the GCD in both groups

( x - 5 ) ( x + 3 ) = 0

x = 5 , -3

The smallest one out of these zeros is -3.

Hope it helps! :)

User GeoO
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