Question

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

Answer 1

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

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 = (-b\pm √(b^2 -4ac))/(2a)`

Using the quadratic equation to solve for the roots;

`x = (-6\pm √(6^2 -4*2*3))/(2*2)\\x = (-6\pm √(36 - 24))/(4)\\x = (-6\pm √(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