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Advanced Math/writing equation from a parabola

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Expert: Sherman D. - 11/11/2008


Question
How do you determine the coefficient for the equation of a parabola?

Answer
you need to plug in some points and i can show you how to do this.

basically you use y = ax^2 + bx + c

plug in the values for x and y, then do that again for the next 2 points, then try and solve for a and b. if you have the c(or y-intercept) this would be even easier.

so if you have

(1,2)
you have
2 = a + b + c, whatever c is
so now this gives us a = -b - c + 2

so now on to the next coordinates

(2,3)
3 = 4a + 2b + c
3 = 4(a + (1/2)b + (1/4)c)
(3/4) = a + (1/2)b + (1/4)c
a = (-1/2)b - (1/4)c + (3/4)

now solve for b, then plug that in for b into the a = problem, then plug both values in for a and b and see if it works out.

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Sherman D.

Expertise

I can answer questions dealing in mathematics of all kinds except for Physics and Calculus, but i can answer questions in Pre-Calculus and Chemistry. I can also answer questions in Recipes of all kinds. I can find games cheats/walkthroughs, but i can`t find a specific game online or offline. I can also do history and recipes for alcoholic beverages.

Experience

Mathematics, Recipes, History, and Games.

Education/Credentials
High School graduated. I graduated with honors, and i was in Beta Club for a year and a half.

Awards and Honors
Principle's list and A and B honor roll in high school only.

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