[help4m]

There are 46 legs in a zoo exhibit. Every animal has either two or four legs.
List two possible choices for the number of each type of animal in the exhibit.
The number of two legged animals is 2 more than the number of four legged animals. How many of each are in the exhibit.
The number of legs in the exhibit increases by 4. what might account for this increase

[Celine91]

let x = number of animals with two legs
and y = number of animals with four legs

The total number of legs is 46, this can make a simple equation:

2*x + 4*y = 46 , there are many possible choices, listing two:

x = 5 and y = 9 /// x = 7 and y = 8
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The next given makes another simple equation: x = y + 2
So far we have a system of two equations with two unknowns:
2*x + 4*y = 46... (1)
x - y = 2... (2)
Solving for x and y ---> x = 9 and y = 11
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if the number of legs increases by four, it can be one of two reasons:
1- the number of two legged animals increased by 2
2- the number of four legged animals increased by 1
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