# Math

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A math teacher drove by a playground that was full of boys and dogs.The teacher notice there were a total of 40 heads and 100 feet. Hom many boys and how many dogs were there?

• Math -

Let x = boys and y = dogs

x + y = 40, then x = 40-y

2x + 4y = 100

Substitute 40-y for x in second equation and solve for y. Insert that value into the first equation and solve for x. Check by inserting both values into the second equation.

• Math -

10 dogs
30 kids

• Math -

2-4=2-=+y=y765

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