Question

Suppose that in one week, your company takes in $2,220 in sales at one of its cell phone stores. The price breakdown per phone is as follows:
Cell phone model A4: $35
Smartphone Z20: $50
Suppose that a total of 51 phones were sold.
Set up the system of equations that needs to be solved to determine how many of each type of phone were sold. Give a clear definition of the variables in the system.
Solve the system of equations, showing clearly how the solution was determined, and state the results clearly in light of the real-world situation.
Verify your results of the 2 linear eq by grap

Answer 1

ok...cell phone model A4 will be represented as a, and smartphone Z20 will be represented as b.

35a + 50b = 2220
a + b = 51

do you understand this so far?

Answer 2

Yes I do

Answer 3

ok, so now let's focus on the second equation to find out what a is. to find out what a would equal, subtract b from both sides to get 51 - b.
so a = 51 - b

Answer 4

now we can substitute 51 - b in our first equation. 35(51 - b) + 50 b = 2220
do you know what to do now?

Answer 5

50b*

Answer 6

I think I do. Can you go a little further for me?

Answer 7

sure. use the distributive property to distribute the 35 into the parentheses first

Answer 8

Ok.

Answer 9

tell me what you get so i know you're doing it lol

Answer 10

So far I have 2220=35+50.

Answer 11

you don't have the variables in there

Answer 12

and you didn't do the distributive property

Answer 13

I'm also transforming this into x and y.

Answer 14

do you know how to distribute?

Answer 15

the letter of the variables doesn't matter. just make sure you tell me which is which

Answer 16

Okay, so I've gotten the following placed as well 2220=35*(51-y)+50*y

Answer 17

Let me know how I'm doing so far.

Answer 18

ok, so do know how to distribute?

Answer 19

I guess I don't quite understand how to distribute?

Answer 20

Here is what I've gotten so far 2220=1785+15*y; 15*y=2220-1785; 15*y=435
y=435/15
y=29