174 is the missing number
Length (L): 2w + 6
width (w): w
Perimeter (P) = 2L + 2w
240 = 2(2w + 6) + 2(w)
240 = 4w + 12 + 2w
240 = 6w + 12
228 = 6w
38 = w
Length (L): 2w + 6 = 2(38) + 6 = 76 + 6 = 82
Answer: width = 38 ft, length = 82 ft
You would use the distributive property with the negative. So the second x becomes negative, but since the 7 is already negative it becomes positive. Think of it as if you put the two dashes together you can make a plus sign.
One possible system is
1x + 3y = 4
2x + 6y = 8
Note how 2 is twice as large as 1, 6 is twice as large as 3, and 8 is twice as large as 4.
In other words, the second equation is the result of multiplying both sides of the first equation by 2.
1x+3y = 4
2*(1x+3y) = 2*4
2x+6y = 8
Effectively the two equations in bold are the same which produces the same line. The two lines overlap perfectly to intersect infinitely many times. An intersection is a solution.
To work this out all you need to do is 108 divide by 7.
The answer would be 15.43
Therefore he would eat 15.43 pounds or you could round it down to 15 pounds.
