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Please explain, thank you

Please explain, thank you-example-1
User Gil Margolin
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1 Answer

11 votes
11 votes

Answer:

C. 2.

Explanation:

The graph descends from the left so the coefficient of the leading term is negative. It is also a cubic equation with zeros of -20, about 6.5 and about 13. so we can write the equation as below. The last 2 values can only be guessed because the x axis only shows values which are multiples of 5.

f(x) = a(x + 20)(x - 6.5)(x - 13) where a is a negative constant.

(This is only an approximation).

By the Remainder theorem, when the expression is divided by (x + 10):

f(-10) = -20 so we have

-20 = a (-10 + 20)(-10-6.5)(-10 - 13)

(10)(-16.5)(-23)a = -20

a = -20 / (10)(-16.5)(-23)

a = -0.0053

When the equation is divided by (x - 10) then f(10) is the remainder so substituting we have as the remainder:

-0.0053(10+20)(10-6.5)(10 -13)

-0.0053 * 30 * 3.5 * -3

= 1.7 approximately.

Looks like the answer is 2.

User Unknownsatan
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2.9k points