Rita, ali, and deandre sent a total of 85 text messages during the weekend. Deandre sent 3 times as many messages as ali. Rita sent 5 more messages than ali. How many messages did they each send?
You would use matrix.
r+a+d=85
0r- 3a+d=0
r- a+0d=5
r=21
a=16
d=48
Rita sent 21 text messages, Ali sent 16 text messages, and Deandre sent 48 text messages.
