Question

Which of the following graphs is described by the function below ?

Answer 1

Answer:

The point of interception of the graph and x axis are -2.366 and -0.634.

The only graph that satisfy this conditions is Graph A

Step-by-step explanation:

Given the equation;

$y = 2x^2 + 6x + 3$

at y = 0

$2x^2 + 6x + 3=0$

the roots of the quadratic equation (at y =0) can be calculated using the quadratic formula;

$x = \frac{-b\pm \sqrt{b^2 -4ac}}{2a}$

Using the quadratic equation to solve for the roots;

$x = \frac{-6\pm \sqrt{6^2 -4*2*3}}{2*2}\\x = \frac{-6\pm \sqrt{36 - 24}}{4}\\x = \frac{-6\pm \sqrt{12}}{4}\\so, we have \\x = -2.366\\or\\x = -0.634$

Therefore, the point of interception of the graph and x axis are -2.366 and -0.634.

The only graph that satisfy this conditions is Graph A