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I need help asap my pc is about to restart in 9 mins just answer it no explanation I just want to know if my answer is good

User Shijin TR
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1 Answer

13 votes
13 votes

Step-by-step explanation:

The equation of a parabola has the following form:

f(x) = ax² + bx + c

Where a, b, and c are constant values.

If a is positive, the parabola opens up and if a is negative the parabola opens down. Additionally, the value of c is the y-intercept of the parabola, it is the point where the graph crosses the y-axis.

Therefore, if the equation of the parabola is:

f(x) = -x² + x - 5

We get that a = -1, b = 1, and c = -5

Then, since a is negative, the parabola opens down and since c is -5, the y-intercept of the parabola is -5.

Finally, the x-coordinate of the vertex of a parabola can be calculated as:


x-\text{coordinate = }(-b)/(2a)=(-1)/(2(-1))=(-1)/(-2)=0.5

So, the y coordinate can be calculated as:


\begin{gathered} f(x)=-x^2+x-5 \\ f(x)=-0.5^2+0.5-5 \\ f(x)=-4.75 \end{gathered}

Then, the vertex of the parabola is the point (0.5, -4.75)

RT

User Ricardo Pardini
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