Curve of Best Fit

What is the line of best fit?

• f(x)= 5x+1.82
• cannot be determined
• f(x)= 1.82x + 5.02
• f(x)= 1.1x + 4.2

Determine which function best fits the given data?

• linear

• quadratic

• Neither

The table shows the average braking distance of a car at various speeds.  Use a quadratic model to predict the breaking distance at 70mph.  

• 245 ft
• 225 ft
• 285 ft
• 265 ft

The table shows the height of a tree for various years after it was planted. Using the line of best fit, how tall would the tree be 30 years after it was planted?

• 22 feet

• 23 feet

• 36 feet

• 37 feet

The height a toy rocket is above the ground is recorded for several times after it was launched. What is the coefficient of x² in the curve of best fit equation?

• -5.43

• 5.43

• 54.81

• -2.43

The height a toy rocket is above the ground is recorded for several times after it was launched. Approximately how long after it is launched does the rocket reach its maximum height? Use the curve of best fit.

• 4 seconds

• 5 seconds

• 6 seconds

• 10 seconds

Find the quadratic equation for the relationship of the horizontal distance and the height of the ball.

• -18x² + 2.11x + 4.21
• -.06x² +1.06x + 7.9
• -6x² +1.06x + 79
• -.12x² + 2.11x + 4.22

Calculate the quadratic regression function for this table of values to the nearest tenth.

• f(x) =
   2x² - 9x + 10
• f(x)=
   3x² + 9x - 10
• f(x) =
   3.1x² - 9.2x - 10.3
• f(x) =
  2.1x² - 8.6x + 10.1

Shown is a residual plot. Would a quadratic regression model of the data be most appropriate?

• YES

• NO

Which function is quadratic?

• f(x)

• h(x)

• g(x)