Answer:
8 ft.
Step-by-step explanation:
The formula for area of a square is:

We are given the area of 64 square feet.

Each side should be 8 ft.
Hope this helps.
We can solve this by setting up a system of equations. We will use x for the $3 boxes and y for the $5 boxes:
x+y=34
3x+5y=130
We can use the elimination method by multiplying the first equation by 3:
3x+3y=102
3x+5y=130
0x-2y=-28
y=14
We can then plug this number back into one of the original equations to solve for x:
x+14=34
x=20
We can check these answers by plugging them into the equations:
20+14=34
34=34
(3)(20)+(5)(14)=130
60+70=130
130=130
Therefore, there are 20 of the $3 boxes, since we originally said that x would be the $3 boxes.
Answer:
y=2x+1
Step-by-step explanation:
A(1;3) and m=2
y-yA=m(x-xA)
y-3=2(x-1)
y-3=2x-2
y=2x+1; or 2x-y+1=0
Answer:
B
Step-by-step explanation: