Question

Which quadratic regression equation best fits the data set?

Answer 1

y = 1.87x² - 5.16x + 10.54

Explanation:

I have attached the scatterplot of the data with each graph drawn on it.

We can see that the one that fits best is the first equation,

y = 1.87x² - 5.16x + 10.54.

Answer 2

Answer:
`y = 1.87x^2 -5.16 x + 10.54`

Explanation:

Since the general quadratic equation is,

`y = ax^2 + bx+c`

Here the given table is,

x 1 2 3 4 5 6 7

y 5.9 8.9 13.4 20.1 30.1 45.1 67.7

By the graphing calculator,

a = 1.87024 ≈ 1.87

b= -5.15833 ≈ -5.15

c = 10.5429 ≈ 10.54

By putting the values of a, b and c,

The required quadratic equation is,

`1.87 x^2 -5.15x + 10.54`

⇒ First Option is correct.