I have difficulty with solving for 2 unknown/

Question

Farmer Floran has roosters and horses. The animals have a total of 88 feet and 40 wings. How many roosters and horses are there?

Is this the correct set up: 88x+40y=128

Answer 1

Let x = number of roosters

y = number of horses

Concerning the fact that there are 88 feet involved, each horse has 4 "feet", each rooster 2:

2x + 4y = 88

Concerning the fact that there are 40 wings involved, each horse has 0 wings, each rooster 2

2x + 0y = 40. The 0y is shown to emphasize that horses have 0 wings.

Now solve this system. The 2nd equation is easily solved for x: x=20.

Substitute 20 for x in first equation and solve for y and you have your solutions.

Answer 2

This type of problem requires that you set up 2 equations in 2 unknowns.

r = number of roosters with 2 feet and 2 wings each

h = number of horses with 4 feet and no wings

There are 88 feet total, so

2r + 4h = 88

There are 40 wings total, so

2r = 40

These are your 2 equations in r and h. Get the value of r from the second equation, and then plug it into the first equation to get h. I get

r = 20

h = 12

Test the answer.