3 years ago

Solve 3x + 5y= 27.5 2x +3y =16 By elimination. What is the solution?

1 answer:

4 0

3x+5y=27.5 ...(1)
2x+3y=16 ...(2)
multiply (1)by 2 and (2)by 3
6x+10y=55 ...(3)
6x+9y=48 ...(4)
subtract (4) from (3)
6x+10y-6x-9y=55-48
y=7
from (2)
2x+3(7)=16
2x=16-21
2x=-5
x=-5/2=-2.5

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