Question

You can model an arch at your school using the equation $y=-0.5\left(x+4\right)\left(x-4\right)$ , where $x$ and $y$ are measured in feet. The x-axis represents the ground. Find the width of the arch at ground level.

Answer 1

8feet

Explanation:

Given the equation that models the arch of a school expressed as;

`$y=-0.5\left(x+4\right)\left(x-4\right)$`

If the x axis represents the ground;

At the ground level, x = 0

Substitute x = 0 into the equation to get y;

y = -0.5(0+4)(0-4)

y = -0.5(4)(-4)

y = -0.5 * -16

y = 8ft

Hence the y axis at the ground level is 8feet