x = the number of humans and y = the number of horses.
x+y=74
2x+4y=196
Because the number of humans and horses together is 74, and the total number of legs (2 per every human, x, and 4 per every horse, y) is 196. Then, just use elimination to solve.
\(-2(x+y=74)\\2x+4y=196\\\\-2x-2y=-148\\2x+4y=196\\\\2y=48\\y=24\)
So, now that you have y, you can plug it into the first equation to find x:
\(x+y=74\\x+24=74\\x=50\)
So, x = 50 and y = 24, so there are 50 humans and 24 horses.
The correct answer is B.
