Answer:
The point at which the banner should be attached to the archway is going to be given by the point(s) at which the two equations intercept:
y = -x^2 + 6x and 4y = 21 − x
Solving the system of equations, we find that they intercept at: (1, 5) and (5.25, 3.938)
Therefore, the banner should be attached to the archway at the points (1, 5) and (5.25, 3.938)
