SOLUTION: I need your help! Problem 1. Elimination method. Type an integer or a decimal 0.05x+0.25y=66 0.15x+0.05y=72 On this problem I keep coming up with(x, y) = (3, 5,-0.5) and e

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Question 174118: I need your help! Problem 1. Elimination method. Type an integer or a decimal
0.05x+0.25y=66
0.15x+0.05y=72
On this problem I keep coming up with(x, y) = (3, 5,-0.5) and each time the answer is wrong. What am I doing wrong?

2. Soybean meal is 18% protein: cornmeal is 9% protein. How many pounds of each should be mixed together in order to get 360-ld mixture that is 17% protein.
Pounds of cornmeal that should be in mixture?
Pounds of soybean meal should be in mixture?
Found 2 solutions by nycsub_teacher, josmiceli:
Answer by nycsub_teacher(90) (Show Source):
You can put this solution on YOUR website!
2. Soybean meal is 18% protein: cornmeal is 9% protein. How many pounds of each should be mixed together in order to get 360-ld mixture that is 17% protein.
Pounds of cornmeal that should be in mixture?
Pounds of soybean meal should be in mixture?

first mixture + second mixture = total mixture

0.18x + 0.09x = 360(0.17)
0.18x + 0.09x(360 - x) = 0.17(360)
Can you take it from here?

Answer by josmiceli(19441) (Show Source):
You can put this solution on YOUR website!

What I would do is multiply both equations by
to get rid of all decimals
(1)
(2)
Now multiply (2) by and subtract (1) from it
(2)
(1)
(3)

Substitute this into ((1) or (2)
(1)

The answer is and
check:
(2)

OK
---------------------------
Let = pounds of cornmeal reeded
Let = pounds of soybeans needed
Given is
lbs
In words:
(pounds of protein from soybeans) + (pounds of protein from cornmeal)
divided by (total pounds of mixture) = % protein in mixture

multiply both sides by

Multiply both sides by
(1) and, given is
(2)
Multiply (2) by and subtract (1) from (2)
(1)
(2)
(3)
and,since

40 pounds of cornmeal and 320 pound of soybeans are needed
check:
(1)

OK