Which order pair dose not represent a point on the graph of y=3x^2-x+7?

Question

1.(-1.5,15.25)

2.(0.5,7.25)

3.(1.25,10.25)

4.(2.5,23.25)

Answer 1

Plug and Chug!! Check each point independently that is plug in the respective x coordinate to get the f(x) which is the function of the respective x value.

For the 1st point I plug in -1.5 = x so f(x)= 3((-1.5)^2)-x+7= 3(2.25)-(-1.5)+7= 7.75+1.5+7= 16.25

but 16.25 is not equal to 15.25 which is the given f(-1.5) from the given points.

Therefore 1. (-1.5, 15.25) is not the correct point on the given function= answer!!

Answer 2

Plug in the values of each (x,y) pair to see if the equation is true.

1. 3*(-1.5)^2 - (-1.5) + 7 = 15.25. True.
2. 3*(0.5)^2 - (0.5) + 7 = 7.25. True.
3. 3*(1.25)^2 - (1.25) + 7 = 10.4375 ≠ 10.25
4. 3*(2.5)^2 - (2.5) + 7 = 23.25. True.