first subtract the last equation from the first. this gives:-
-x + y = -8 .....................(1)
Then multiply the first equation by 2 and add it to the 2nd equations This gives
9x = 18
so x = 2
and from equation (1) y = -8 + 2 = -6
Substituting for x and y in the second equation
z = (24 -5(2) -12) / 2 = 1
Answer is choice b.
I believe y=-x+8 cause you would take the 2 then subtract it to the 16 for it to turn into 2y=-2x+16 then you take the 2y and divide
Example: (1/5)/(4/13)=(1/5)*(13/4)=13/20
Check the picture below.
neverminding for a few seconds the volume of the cylinder, the percentage in the height used by the water will be the same as the percentage of its volume. We know the total amount or 100% of the height is 14, so what is 11 in percentage?

Perimeter=2L+2W, in this case L=80+2(25) and W=170+2(25) so
P=2(L+W)=2(80+50+170+50)
P=2(350)=700m