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anonymous
 one year ago
3x+(5/2)y=21
x+2y=14
can someone help me solve this plzzz.
anonymous
 one year ago
3x+(5/2)y=21 x+2y=14 can someone help me solve this plzzz.

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kropot72
 one year ago
Best ResponseYou've already chosen the best response.0You can find x in terms of y by rearranging the second equation as follows: x + 2y = 14 Therefore: x = 14  2y Do you understand this first step?

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0your subtracting 2y from both sides?

kropot72
 one year ago
Best ResponseYou've already chosen the best response.0Yes, you are correct. Now we can plug this expression for x into the first equation 3x + (5/2)y = 21 giving 3(14  2y) + (5/2)y = 21 which expands to 42  6y + (5/2)y = 21 Can you now solve this last equation to find the value of y?

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0first I think is 21  42 which is 2. 6y + (5/2)y= 21 after that i'm kinda confused

UsukiDoll
 one year ago
Best ResponseYou've already chosen the best response.1\[3x+ \frac{5}{2}y=21\] \[x+2y=14\] I think dealing with the fraction is a chore... maybe we can multiply 2 throughout the first equation so we can have whole numbers to work with

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0yea im not good with fractions

UsukiDoll
 one year ago
Best ResponseYou've already chosen the best response.1\[3(2)x+ \frac{5(2)}{2}y=21(2)\] \[6x+ 5y=42\] \[x+2y=14\]

UsukiDoll
 one year ago
Best ResponseYou've already chosen the best response.1we could use subsitution by using the second equation x=142y and then plug it into the first equation

kropot72
 one year ago
Best ResponseYou've already chosen the best response.0The equation simplifies to  (7/2)y = 21 Now you can multiply both sides by 2 to give 7y = 42

kropot72
 one year ago
Best ResponseYou've already chosen the best response.0yes y = 6 is correct.

UsukiDoll
 one year ago
Best ResponseYou've already chosen the best response.1\[8412y+5y=42 \rightarrow 847y=42\] \[7y=4284 \rightarrow 7y=42 \rightarrow y=6\]

UsukiDoll
 one year ago
Best ResponseYou've already chosen the best response.1so now we can plug y = 6 back into one of the equations.. let's try the second equation x+2y = 14

kropot72
 one year ago
Best ResponseYou've already chosen the best response.0Which shows there is more than one way to skin a cat, if you forgive the analogy :)

UsukiDoll
 one year ago
Best ResponseYou've already chosen the best response.1ewwww I own cats in real life

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0x=2 n I had a cat once

UsukiDoll
 one year ago
Best ResponseYou've already chosen the best response.1yes so x = 2 and y = 6 we can plug it back into the original equations to see if we have the right answer.. I know we do because 2+2(6)=14 2+12=14 14=14

UsukiDoll
 one year ago
Best ResponseYou've already chosen the best response.13(2) +5/2(6/1) = 21 6+(30/2)=21 6+15=21 21=21

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0dw:1437803748984:dw
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