Question

latoya surveyed her friends to see how many pets they own. Her 6 friends have a total of 11 cats and birds. If there are a total of 36 legs how many cats and birds are there?

Answer 1

First we make 2 equations from the given info
let c = cats & b = birds
$c + b = 11$
$4c + 2b = 36$
^ because cats have 4 legs and birds have 2

now next we want to solve for one of the variable in the first equation, then plug it into the second one
so..
$b = 11 - c$
now plug it in
$4c + 22 - 2c = 36$
simplify
$2c = 14$
$c = 7$
now all we have to do is put 7 back into our first equation
$7 + b = 11$
$b = 4$

7 cats
4 birds