Since you need an isolated variable to use the substitution method, we need to re-arrange one of the equations. This will probably be easiest to do with the first one.
Add 5y to both sides of the first equation.
x=10+5y
Now, in the second equation, put in 10+5y in any spot that has an x.
2(10+5y)-10y=20
Distribute the 2 to both numbers in the parenthesis.
20+10y-10y=20
Combine like terms.
20=20
This means that the two equations are actually the same. You can see this if you multiply the whole first equation by 2
2(x-5y=10)
2x-10y=20, which is the same as the second equation. Therefore, the two equations are actually the same one.
Answer:
24% saline
Step-by-step explanation:
Find how much saline is in both solutions:
7(0.27)
= 1.89
3(0.17)
= 0.51
Add this together:
1.89 + 0.51
= 2.4
Since there are 10 quarts in total, the concentration of the mixture can be found by dividing 2.4 by 10:
2.4/10
= 0.24
So, the concentration of the mixture is 24% saline
Answer:
how many bags because you just said bags?
The rate of change per year is 3 million per year.
Answer:
about 6.66666 inches
Step-by-step explanation:
It says you're in college why do you need help with such a simple problem?