Math 1 January 6

Systems by Elimination

January 6, 2021

Example 1

 $3x+5y=10$  
 $5x+7y=10$  

Example 2

 $10x+7y=-4$  
 $15x+3y=9$  

Example 3

 $2x-3y=-11$  
 $3x+2y=29$  

Example 4

 $5x+7y=-1$  
 $4x-2y=22$  

Example 5

The sum of two numbers is 18. The sum of the greater number and twice the smaller number is 25. Find the numbers.

Example 6

Suppose a band at another school sells erasers for $2 per package and pencils for $5 per package. The band sells 220 packages in all and earns a total of $695. Write a system of equations to find the number of each type of package sold.

Example 7

Grandma’s Bakery sells single crust apple pies for $6.99 and double crust cherry pies for $10.99. The total number of pies sold on a busy Friday was thirty-six. If the amount collected for all the pies that day was $331.64, how many of each type of pies was sold?

Example 8

A promoter priced tickets to a concert as follows: $17 when purchased in advance and $20 when purchased at the door. The total number of tickets purchased was 514, and ticket sales totaled $9,158. How many tickets were sold at the door?