3x+6y=30, 2x+7y=29 using elimination method

1 answer:

8 0

Solutions

----- Solve using Elimination

$3x+6y=30

2x+7y=29$

$6x+12y=60

2x+7y=29$

$6x+12y=60

6x+21y=87$

$
-9y=-27
 
$

$y=3

 

 
$

Substitute y=3 into any of the two equations above

$
6x+12*3=60
 
$

$6x+36=60$

$6x=60-36

 

 
$

$6x=24$

$x= 24 / 6$

$x=4$

$x=4

y=3$

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The heights of two similar cylinders are 3cm and 4cm respectively. The total area of the bigger cylinder is 400cm².Calculate the

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