Answer:
In romania I was doing this in the 6th grade
First task:
To determine this we need to make difference between system that doesn't have solution and system that has infinite number of solution. If when solving equations we get 0 = 0 that means system has infinite number of equations.
If we get 0 = some number that means that system doesn't have solution.
Multiplying first equation of second system by 2 and adding it to second equation we get 0=0 which means that this system has infinite number of solutions.
Answer is second system
Second task:
For this we need to set a system of equations and solve it. System looks like this:
x + y = 224
x*12 + y*8=2520
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x represents older than 18 and "y" 18 and younger than that.
first equation we multiply with -12 and sum it with second.
-4y = -168
y=168/4 = 42
Answer is 42.
0.06 x 0.5 = 0.03 (I think that is what you're asking)
Answer:66 hours of video games in three weeks!
Step-by-step explanation:First you would multiply 6 by 2 because the weekend refers to Saturday and Sunday which are two days,when you multiply 6 by 2 you get 12.Next you would multiply 2 by 5 because the problem says 2 hours each day of the week,when you multiply 2 by 5 you get 10.Then you add 10 and 12 which gets you to 22.Last but not least you multiply 22 by 3 because the question says how many hours does mr.danie spend playing video games over <em>3 weeks,</em>which bring you to 66!
I hope I helped!
