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Find the zeros of the quadratic function: f(x) = x2 + 8x – 20 0 = ax2 + bx + c What is the factored form of the function? What are the zeros of the quadratic function?

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=> f(x) = x² + 8x - 20 = 0

=> x² + 8x - 20 = 0

=> x² + 10x - 2x - 20 = 0

=> x(x + 10) - 2(x + 10) = 0

=> (x + 10)(x - 2) = 0

=> x = -10 and 2


Therefore zeroes of quadratic function are :- - 10 and 2
User FiberOptics
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The factored form of the equation is f(x) = (x - 2)(x + 10), which makes the zeros of the function x = -10 and x = 2.


In order to factor a quadratic like this, you must find factors of the constant (in this case -20). The pairs of factors are listed below.


1 and -20

-1 and 20

2 and -10

-2 and 10

4 and -5

-4 and 5


Now we must pick out the pair that add to the coefficient of x.


1 and -20

-1 and 20

2 and -10

-2 and 10

4 and -5

-4 and 5


Once you've picked out those numbers, you can place each in a parenthesis with x.


f(x) = (x - 2)(x + 10)


Then to find the zeros to the equation, set each parenthesis equal to 0 and solve.


x - 2 = 0

x = 2


x + 10 = 0

x = -10

User Nirmal Ram
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