Answer:
goldfish
Step-by-step explanation:
for converting km to meters
1 km = 1000 m
5807 km = 1000 × 5807 m
= 5807000m ...
for converting cups to gallons
1 cup = 0.0625 gallons
2144 cups = 0.0625 × 2144 gallons
= 134 gallons
Solve by substitution


Just plug in y=-x-1 into y+x=3
So we get:

Simplify that:

And since that is not true, that means this system of equations has no solutions!
First you need to figure out the slope:
y2-y1/x2-x1=(1+5)/(-5-7)=-1/2
y+5=-1/2(x-7)
y=-1/2x-3/2
Let's first break it down to the time 8 people need for one wall. That would be 10 minutes, right? If one person would have to do it in stead of 8, you'd expect him to take 80 minutes.
To paint 7 walls, he would nee 7x80 = 560 minutes. 10 people would do that 10 times faster, ie., 56 minutes.
I know puzzles like these always have a mindtrick. Did I miss anything?? ;-)