The number three (3) when decreased by fifteen (15) is four (4) times its opposite.
In this exercise, you're required to solve for an unknown number by using a variable to represent the number in relation to the known variables (constants) and representing it as an algebraic expression.
Translating the word problem into an algebraic expression, we have;
Rearranging the algebraic expression by (collecting like terms), we have;
Dividing both sides by 5, we have;
<em>x = 3</em>
<em>Therefore, number </em><em>three</em><em> </em><em>(3) </em><em>when </em><em>decreased</em><em> by </em><em>fifteen (15)</em><em> is </em><em>four (4) </em><em>times its </em><em>opposite.</em>
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