X + y = 40.....multiply by -4
4x + 6y = 180
-------------------
-4x - 4y = -160 (result of multiplying by -4)
4x + 6y = 180
------------------add
2y = 20
y = 20/2
y = 10 <===
x = 30
the answer is 1200 millimeters per hour
Hope you could understand.
If you have any query, feel free to ask.
Answer:
1/2
Step-by-step explanation:
output devided by input
Subtract*************************************************************88888