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anonymous
 4 years ago
how to do 7x  3y = 20

5x + 3y = 16
with elimination?
anonymous
 4 years ago
how to do 7x  3y = 20  5x + 3y = 16 with elimination?

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anonymous
 4 years ago
Best ResponseYou've already chosen the best response.0the 3y cancels out, so 7x+5x=12x and 20+16= 36so the new equation is 12x=36

anonymous
 4 years ago
Best ResponseYou've already chosen the best response.0add two equations and u will get 12x=36 so x=3, put this value of x in any equation, u will get the value of y

anonymous
 4 years ago
Best ResponseYou've already chosen the best response.0I thought with elimination you were supposed to multiply one of the equations to make it the same as the other? Im not completely sure thats why i asked here :P

anonymous
 4 years ago
Best ResponseYou've already chosen the best response.0Well, you do need to multiply one or both equations to make the coefficient of one of the variables same (constant before the variable). In this case, the coefficient of y is already the same (3). So, you don't need to multiply to do elimination.

anonymous
 4 years ago
Best ResponseYou've already chosen the best response.0If you had for example x + 2y = 5 2x + y = 7 Then, you will have to multiply the second equation by 2 to eliminate y. Or, multiply the first equation by 2 to eliminate x.
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