Algebra 1 Parabola

Question

A parabola passes through the points (-4,105) (3,14) and (7,94). Write the equation of the quadratic. Then, find the x-value, when y=329. Be thorough, and show your work.

Answer 1

A parabola passes through the points (-4,105) (3,14) and (7,94). Write the equation of the quadratic. Then, find the x-value, when y=329. Be thorough, and show your work.

You should use these equations:

Y-Y = X-X and Y-Y/X-X

Choose two points:

105-14/-4-3): your slope

Then plug in this for m after writing y-105= x-+-4)

Do the same for (7, 94) and then set the equations equal to zero to get the x values.

When looking for y at 329 plug y in and simplify.

Answer 2

You must set up a set of 3 linear equations in A, B, and C where those are the coefficients of the parabolic function. You get those equations by using the points given.

This will be messy!!

Once you have the coefficients you can get the value of x by solving the equation

Ax² + Bx + C = 329.

Good luck!