1. If A=lw and you know A=200ft then find what l and/or w are:
"the length of the garden is 1 foot less than three times the width"
so now you know A and L (in terms of w). Now you just combine the equation and solve for w using A=(l)w. Then you use the width you just found and solve for length and your done.
2. Is the question:
Regardless of your current equation, X intercepts are when the function crosses the X axis which means y=0 at those points. Solve the equation accordingly.
example find the x intercepts of
just solve for:
which means that And
then solve the equations. So the x intercepts are x=2 bc when x=2 y=0 and x=-2 bc when x=-2 y also equals zero