f(x)=−(x+1)(x+7)The function represents a parabola in the xy-plane. Which of the following is an equivalent form of f in which the y-intercept of the graph of f appears as a constant or coefficient?Choose 1 answer:(A) f(x)=−(x+4)2+9(B) f(x)=−(x+4)2−9(C) f(x)=−x2+8x+7(D) f(x)=−x2−8x−7
Q. f(x)=−(x+1)(x+7)The function represents a parabola in the xy-plane. Which of the following is an equivalent form of f in which the y-intercept of the graph of f appears as a constant or coefficient?Choose 1 answer:(A) f(x)=−(x+4)2+9(B) f(x)=−(x+4)2−9(C) f(x)=−x2+8x+7(D) f(x)=−x2−8x−7
Expand the given function: We need to expand the given function f(x)=−(x+1)(x+7) to find the equivalent form that shows the y-intercept.f(x)=−(x2+7x+x+7)f(x)=−(x2+8x+7)Now, distribute the negative sign.f(x)=−x2−8x−7
Find the y-intercept: The y-intercept of a function is the value of f(x) when x=0. Let's find the y-intercept of the function f(x)=−x2−8x−7.f(0)=−(0)2−8(0)−7f(0)=−7The y-intercept is −7.
Compare with given choices: Now, we need to compare the expanded form of f(x) with the given choices to see which one has −7 as the constant or coefficient that represents the y-intercept.(A) f(x)=−(x+4)2+9 does not have −7 as a constant or coefficient.(B) f(x)=−(x+4)2−9 does not have −7 as a constant or coefficient.(C) f(x)=−x2+8x+7 does not have −7 as a constant or coefficient.(D) f(x)=−x2−8x−7 has −7 as a constant, which is the y-intercept we found.
Identify the correct answer: The correct answer is (D) f(x)=−x2−8x−7 because it is the equivalent form of the given function and it shows the y-intercept as a constant or coefficient.
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