I have a chem lab and we need to find the amount of two different weight pennies in a film canister of 15 pennies just by the weight.
Do i just set up to equations like this:
3.1x+2.51y=43.97
x+y=15
??
3.1x + 2.51y = 43.97
x + y = 15
I don't know if these are the two correct equations; but, if they are, one way to solve them is by solving the second equation for x and then substituting that value in the first equation:
x + y = 15 ---> x = 15 - y
3.1x + 2.51y = 43.97 ---> 3.1(15 - y) + 2.51y = 43.97
46.5 - 3.1y + 2.51y = 43.97
46.5 - 0.59y = 43.97
-0.59y = -2.53
y = 4.29
Substituting that value into the equation x = 15 - y ---> x = 15 - 4.29 ---> x = 10.71
3.1x + 2.51y = 43.97
x + y = 15
I don't know if these are the two correct equations; but, if they are, one way to solve them is by solving the second equation for x and then substituting that value in the first equation:
x + y = 15 ---> x = 15 - y
3.1x + 2.51y = 43.97 ---> 3.1(15 - y) + 2.51y = 43.97
46.5 - 3.1y + 2.51y = 43.97
46.5 - 0.59y = 43.97
-0.59y = -2.53
y = 4.29
Substituting that value into the equation x = 15 - y ---> x = 15 - 4.29 ---> x = 10.71