10. When Raphael solved the system below by using the method of elimination, he changed the second equation to –8x – 2y =-2. What property justifies this manipulation?
8x + 3y = 7
4x + y =1

Acampus club held a bake sale as a fund raiser, selling coffee, muffins, and bacon and eggs sandwiches. the club members charged $1 for a cup of coffee, 3$ for a muffin , and $4 for a back. and egg sandwich. they sold a total of 55 items , easing $119. of the club members sold 5 more muffins than cups of coffee, how many bacon and egg sandwiches he’s did they sell