
Susan L. answered 11/18/23
K-12 Mathematics Coordinator with 20+ Years Teaching Experience
Katherine and Corey are collecting stamps. You start by assigning values:
Katherine: x stamps
Corey: 5x - 23 stamps, where the 5x represents 5 times Katherine's stamps, and the - 23 represents 23 fewer
The two together collect 1129 stamps, so you can setup the equation:
x + (5x -23) = 1129 an equation which models this situation
x + 5x - 23 = 1129 equation written without parentheses
6x - 23 = 1129 combining like terms
+23 +23 addition property of equality, to get variables on one side, numbers on the other
6x 1152
6 6 division property of equality, to solve for x (divide by the coefficient of x)
x = 192 stamps, and by substitution, 5x - 23 = 5(192) - 23 = 937 stamps
Written as a complete sentence:
Katherine collects 192 stamps and Corey collects 937 stamps, for a total of 1129 stamps.