Choose from the following properties to justify each step in the solution for the given equation.
-24 = 5x - 9
-15 = 5x
-3 = x
addition property of equality
subtraction property of equality
multiplication property of equality
division property of equality

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The sum of the speeds of two trains is 720.2 mph. if the speed of the first train is 7.8 mph faster than the second train, find the speeds of each.

Find solution of the linear equation y = 2/3x + 1/3

The ivring berlin learning center would like a possible net profit of $650,000 on its new resource manual it sells to schools. the fixed costs for producing the manual are $780,000 and the variable cost per package is $19.85. if the estimated unit sales are 1,250,000 units, what selling price unit should the ivring berlin learning center try?