The width of a rectangle is 1 unit less than the length. The area of the rectangle is 72 units. What is the width, in units, of the rectangle?

Step-by-step explanation:

Width of the rectangle= W

Length= L

W=(L-1) units

Area= 72 square units

Area of a rectangle= Length*Width

Solving the quadratic equation using the factorization method:

Taking common from the equation:

OR

The length cannot be negative, therefore: Length= 9 units

The question is asking you to find the axis of symmetry, which is the x-value of the vertex. In order to do that you need to factor the function to find the zeros and add the zeros together and divide by two to find the axis of symmetry.
y=-16x^2+608x
y=-16x(x-38)
Zeros: x=0 and x=38
38/2=19
Therefore it takes 19 seconds for the projectile to reach its maximum height.
Hope this helps!