B (second choice) it just makes sense when u think about it
Answer:
The dimensions of the screen are
Length:102 feet
Width: 82 feet
Step-by-step explanation:
we know that
The area of the rectangle (movie screen) is equal to

where
L is the length
W is the width
we have

so
----> equation A
The screen is 20 feet longer than it is wide.
so
---> equation B
substitute equation B in equation A

solve for W

solve the quadratic equation by graphing
the solution is W=82 ft
see the attached figure
Find the value of L

therefore
The dimensions of the screen are
Length:102 feet
Width: 82 feet
Answer:
a.b=[-1]
Step-by-step explanation:
This is a dot product of a and b
a.b =[6,-2,3].[2,5, -1] = [12-10-3] =[-1]