
so.. whatever "x" and "y" amounts are, we know that, added together, they must yield 14lbs
thus x + y = 14
and whatever the cost of each is, 7x + 4y must be 14*5
7x+4y = 70
thus

solve for "x", to see how much of the $7/lb type will be needed
what about the $4/lb one? well, y = 14 - x
Answer:
2n - 10 = 12
Step-by-step explanation:
the difference of twice a number and 10 is equal to 12
= twice a number minus 10 equal to 12
=> 2n - 10 = 12
w = number of weeks
b(w) = number of books read after w weeks
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b(w) = 12 translates to "after w weeks, Katy will have read 12 books" or put another way "Katy will have read 12 books after w weeks". The 'w' is a placeholder for some number
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b(2) = 10 means "Katy has read 10 books after 2 weeks". We use the same basic idea talked about above, but we replace w with 2. At the same time, we use 10 instead of 12.
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b(3) = f means "Katy has read f books after 3 weeks" or "after 3 weeks, Katy has read f books". Like w, the f is a placeholder for some number.
Answer:
-21=24
Step-by-step explanation:
Subtract 24 from 3
-21=8+2^2
Raise 4 to the power of 2
-21=8+16
Add 8 and 16
-21=24
We can factor by grouping like so
3v^2 + 16v + 5
3v^2 + 15v + v + 5
3v(v + 5) + 1(v + 5)
(3v+1)(v+5)
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Check:
(3v+1)(v+5)
w(v+5) ... let w = 3v+1
vw + 5w
v(w) + 5(w)
v(3v+1) + 5(3v+1) .... plug in w = 3v+1
3v^2+v + 15v + 5
3v^2 + 16v + 5
We get the original expression again, which confirms the answer.