Dave is 18 years old.
A number, a variable, or a mix of numbers, variables, and operation symbols make up an expression. Two expressions joined by an equal sign form an equation. Word illustration: The product of 8 and 3. Word illustration: The product of 8 and 3 is 11
Given
Let x be Dave’s age today. Then:
x=3(x+3)-3(x-3)
x=3x+9–3x+9
x=18
Dave is 18 years old.
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