18 ÷ d
2dc
8 + 4x
3x − 1
x2 − 15
4c + 2d
4x − 8
x2 + 15
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The total of eight and four times a number.
Fifteen less than a number squared.
One less than three times a number.
Four times the number of cats plus two times the number of dogs.
The quotient of 18 and d
The product of the number of dogs and cats times 2.