Answer:
Length=87 ft
Width=77 ft
Explanation:
Let
L ----> the length of rectangular movie screen
W ----> the width of rectangular movie screen
we know that
The area is equal to
![A=LW](https://img.qammunity.org/2020/formulas/mathematics/high-school/3j0ob8ofk1s943d3rmpkx8tdoddrtl3gew.png)
![A=6,699\ ft^(2)](https://img.qammunity.org/2020/formulas/mathematics/middle-school/9rf60qtf5ohoo1aq9sk0xs5ryfmp5paeu8.png)
so
----> equation A
----> equation B
substitute equation B in equation A
![6,699=(W+10)W\\ \\W^(2) +10W-6,699=0](https://img.qammunity.org/2020/formulas/mathematics/middle-school/6d7l2gf70fl0lygq1qt5pxo0kmmc0ioni1.png)
Solve the quadratic equation by graphing
The solution is
![W=77\ ft](https://img.qammunity.org/2020/formulas/mathematics/middle-school/aktxpa8cnzgst8sg55fbhrww55lui5ewzm.png)
see the attached figure
Find the value of L
![L=77+10=87\ ft](https://img.qammunity.org/2020/formulas/mathematics/middle-school/t552rov5xzjadqd1rnnri4z5qnb1eubqk0.png)