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A-81.

Write an equation or system of equations to solve the problem below.

Apollo and Zeus are both on diets. Apollo currently weighs $105$ kg and is gaining $2$ kg per month. Zeus currently weighs $130$ kg and is losing $3$ kg per month. In how many months will they weigh the same?

Let $a$ stand for Apollo's weight, $z$ stand for Zeus' weight, and $x$ stand for the number of months.

$a = 105 + 2x$
$z = 130 − 3x$

Set these two equations equal to each other.

$x = 5$ months

Use the eTool below to help you write equations for both Apollo and Zeus to discover at how many months they will weigh the same amount.
Click the link at right for the full eTool version: CCA2 A-81 HW eTool