It is best to use binary linear equations. If you haven't studied binary linear equations, it's not bad to use univariate linear equations.

Example:

Chickens and rabbits are kept together, and * * * has 36 feet. * * * owns 13 animals. How many chickens and rabbits are there?

Solving binary linear equations;

Suppose there are x chickens and y rabbits.

rule

X+Y= 13

(* * * There are 13 animals)

2X+4Y=36

(36 feet)

Then X=8.

Y=5

So chicken eight, rabbit five

Using one-dimensional linear equation:

Suppose there are x chickens, then there are rabbits13-X.

Use the number of feet to form the equation.

2X+4( 13-X)=36

X=8

So chicken eight, rabbit five