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anonymous
 5 years ago
What is the value of x in the solution to the following system of equations? x+y=39 and 3x+4y=136
anonymous
 5 years ago
What is the value of x in the solution to the following system of equations? x+y=39 and 3x+4y=136

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anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0x=y+39 and 4/3y+136/3

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0x+y=39 and 3x+4y=136 y y 4y 4y x=38 3x= 132 /3 /3 x= 66

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0that's not on the answer document

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0well, looking at my answers, the number could be 10,20,29,or30

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Take the two equations, realize that you can add and subtract the two equations from each other. What I mean by that is, you can add x + y = 39 (from the first equation) to 3x + 4y = 136 (from the second) to get 4x + 5y = 175. Now some cleverness comes into play. We want to get one of the variables to cancel. To do this we can multiply either equation by a constant. Lets multiply the first equation by 4 and subtract it from the second. 4x + 4y  (3x + 4y) = 156  136. When you go through and cancel you boil it down to x = 20.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Oh, okay, that makes sense.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0You can also verify your answer if you need to do this on a test. When you arrive at a conclusion, for instance x = 20. Plug 20 in for x in one of the equations and solve for y. From equation 1 we get 20 + y = 39, which we can see y = 19. Now plugging that into equation 2 we get 3(20) + 4(19) = 136 so our answer is correct.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Oh, thanks! I understand.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0mary100 your answer is wrong there is only one answer not to. The correct answer is x=20 it is that answer because you can solve equations by graphing x+y=39 3x+4y=136 Put your answer x x 3x 3x in your calc and graph y=x+39 4y=3x+136 it than you will see 20 divide by 4 than check your y=3/4x+34 answer

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0so I can do this with or without a calculator?

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0You can do it without a calculator but the calculator just checks it

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Coming from someone with a B.S. in Math, you NEVER NEED a calculator, but they are often helpful.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Well, I came from poor schools and back then we never got to use calculators.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0If you do solving equations by graphing you need a calculator but if you do elimination or substitution you totally do not need a calculator

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0thanks, you are great!!
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