Assuming you mean 2x-8y=7, we can start by multiplying the first equation by -2 and adding it to the second (to cross out the x), resulting in -18y=-5. After that, we can divide both sides by -18, resulting in y=5/18. Next, plugging that into 4x-2y=9, we have 4x-10/18=9. Adding 10/18 to both sides, we get 4x=9+10/18. After that, we can divide both sides by 4, resulting in x=(9+10/18)/4=
Answer:
y = 18
Step-by-step explanation:
It’s -9 because when multiplied it’s about -9
I believe there are 20 quarters and 3 nickels.....
Total value of the jar is $5.15.....
Quarters are worth 25 cents
And nickels are worth 5 cents.
First you know that there are 4 quarters in a dollar.
You have 5 dollars so you do 4 x 5 = 20
So five dollars ($5.00) is 20 quarters.
And you still have 15 cents left.
Because quarters are 25 cents the rest are nickels.
Nickels are worth 5 cents so you'd do 5 x 3 = 15.
15 cents!
Add all this together and get $5.15.
So your answer is
There are 20 quarters and 3 nickels in the jar.