SOLUTION: Hello. I am having a question in the CPM Algebra 2 book on pg.179. My chapter, that I am on, is about parabola equations. You can find the problem and any diagrams on hotmath.com.

Algebra ->  Quadratic-relations-and-conic-sections -> SOLUTION: Hello. I am having a question in the CPM Algebra 2 book on pg.179. My chapter, that I am on, is about parabola equations. You can find the problem and any diagrams on hotmath.com.       Log On


   

Question 233345: Hello. I am having a question in the CPM Algebra 2 book on pg.179. My chapter, that I am on, is about parabola equations. You can find the problem and any diagrams on hotmath.com. The question is this...
4-47
"A jackrabbit is jumping over a three-foot-high fence. To clear the fence, the rabbit must start its jump at a point four feet from the fence and will end four feet from the fence"
When drawing this graph and making an equation, I am unsure where to go about this problem, to write this equation. Please help. Much appreciated:)
Answer by Theo(13342) About Me  (Show Source):
You can put this solution on YOUR website!
Let the fence be at x = 0.

Rabbit has to start jump at x = -4 and end jump at x = 4

Rabbit jump will be in the form of a parabola that opens downward and peaks at x = 0.

Parabola that opens down and peaks up needs the a term to be equal to 0.

Quadratic equation models a parabole.

standard form of a quadratic equation is ax^2 + bx + c = 0

Roots have to be x = -4 and x = + 4

Equation would have to be of the form:

(x-4)*(x+4) = 0

Multiply (x-4)*(x_4) to get x^2 - 16 = 0

Multiply that by -1 to get:

-x^2 + 16 = 0

That allows the equation to peak at x = 0 and still cross at x = -4 and x = 4.

Equation will look like the following:

graph%28400%2C400%2C-5%2C5%2C-10%2C30%2C-x%5E2+%2B+16%29