posted by Lee .
You throw a rock off the balcony overlooking your backyard the table shows the height of the rock at different times use quadratic regressin to find a quadratic model for this data.
0 1 2 3 4 5
24 44.2 54.8 55.8 47.2 29
would someone explain this to me had a problem like this before and got it wrong
Judging from your other problems, I think quadratic regression is a bit beyond the current subject matter. (If not so, let me know just what you have studied in regards to quadratic regression.) So let's try a simpler approach.
evidently the equation is
y = ax^2 + bx + 24
plugging in the given values,
20.2 = a + b
30.8 = 4a + 2b
31.5 = 9a + 3b
23.2 = 16a + 4b
5 = 25a + 5b
Solving these equations in pairs, we get
(a,b) = (-4.8,25),(-4.9,25.2),(-4.7,24.6),(-4.8,25) and so forth.
If you're not looking for the best fit, you could use a model like
y = -4.8x^2 + 25x + 24
If this approach is not what you wanted, please clarify.
The y=4.8x^2+25x+24 was correct answer, but I'm not sure how you got that.
no of your business
the actual answer to this is
y=-4.8^2+25x+24 you did not put a negative on it :)
1-7 answers for Factoring quadratic quiz
You're welcome now do good in school kids!
Suppose a parabola has vertex (-4,7). and also passes through the point (-3,8) write the equation in a a parabola vertex form