Answer:
c = 2.4
p = 1.6
Step-by-step explanation:
Given:
5c+4p=18.40
2c+4p=11.20
-1(2c+4p=11.20) <-- Distribute -1 so that you can cancel out p
-2c-4p=-11.20
5c+4p=18.40
+ -2c-4p=-11.20 <-- Add/simplify like terms
3c = 7.2 <-- Isolate c by dividing
c = 2.4
Now that we have c, we can find p
5c+4p=18.40
5(2.4)+4p=18.40 <-- Sub in 2.4 for c
12+4p=18.40 <-- Combine like terms in one side
4p=6.4 <-- Isolate p by dividing
p = 1.6