Question

Which of the following equations describes the graph?

Answer 1

Answer:

The equation that represents the graph is:

                         $y=2x^2-3$

Step-by-step explanation:

We know that the general quadratic equation of the type:

   $y=ax^2+bx+c$

is a upward or a downward parabola depending on a.

If a>0 then the parabola is a upward open parabola.

and if a<0 then the parabola is a downward open parabola.

Hence, the option:

  $y=-2x^2-3\\\\and\\\\y=-2x^2+3$

Hence, the two options are discarded as there leading coefficient is negative but the parabola is open downward.

Hence, we are left with

$y=2x^2+3\ and\ y=2x^2-3$

From the graph, we have when x=0 we have f(0)= -3

Hence, the only option we are left with is:

   $y=2x^2-3$

( Since, in the option:

    $y=2x^2+3$ at x=0 we have y=3≠ -3  )