Question

solve the equation by elimination method

0.4x+0.3y=1.7
0.7x- 0.2y=0.8

Answer 1

$hi....$

$0.4x + 0.3 y= 1.7 \: \: .........(1)$
$0.7x - 0.2y =0 .8 \: \: ..........(2)$

[Multiplying equation no. (1) by 2 and equation no. (2) by 3]

$we \: \: get.......$

$0.8x + 0.6y = 3.4 \: \: ........(3)$
$2.1x - 0.6y = 2.4 \: \: ......(4)$

[ Adding equation no. (3) & (4) ]

0.8x + 0.6y = 3.4
2.1x - 0.6y = 2.4
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2.9x = 5.8

x = 5.8 / 2.9
$x = 2$

[ Substitute x=2 in equation no. (1) ]

$0.4x + 0.3y = 1.7$
$0.4(2) + 0.3y = 1.7$
$0.8 +0 .3y =1 .7$
$0.3y = 1.7 - 0.8$
$0.3y =0 .9$
$y = 0.9/0.3$
$y = 3$
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Solution ..

$x = 2 \: \: \: . \: \: \: y = 3$
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$hope \: this \: helps........$