Answer:
Length=87 ft
Width=77 ft
Step-by-step explanation:
Let
L ----> the length of rectangular movie screen
W ----> the width of rectangular movie screen
we know that
The area is equal to
[tex]A=LW[/tex]
[tex]A=6,699\ ft^{2}[/tex]
so
[tex]6,699=LW[/tex] ----> equation A
[tex]L=W+10[/tex] ----> equation B
substitute equation B in equation A
[tex]6,699=(W+10)W\\ \\W^{2} +10W-6,699=0[/tex]
Solve the quadratic equation by graphing
The solution is [tex]W=77\ ft[/tex]
see the attached figure
Find the value of L
[tex]L=77+10=87\ ft[/tex]