Question

$2x + 3y =14 \: and \: 2x - 3y = 2 \: find \: xy$
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Answer 1

2*4+3*2= 14

2*4-3*2= 2

8= xy ans..

Answer 2

Answer:

2x+3y=14........1

2x-3y=2..........2

Step-by-step explanation:

$2x + 3y = 14 \\ 2x = 14 - 3y \\ x = \frac{14 - 3y}{2}$

Now we know x value

Now we put it in the second equation .

$2x - 3y = 2 \\ = 2 \times \frac{ 14 - 3y}{2} - 3y = 2 \\ = 14 - 3y - 3y = 2 \\ 14 - 6y = 2 \\ - 6y = 2 - 14 \\ - 6y = - 12 \\ - y = - 2 \\ y = 2$

Now easily we can find the value of x

now put the value of y in the first equation .

$2 x + 3y = 14 \\ 2x + 3 \times 2 = 14 \\ 2x + 6 = 14 \\ 2x = 14 - 6 \\ 2x = 8 \\ x = 4$

now find the value of xy

$respectively \: x = 4 \: and \: y = 2 \\ so \: \: \: \: \: \: xy =4 \times 2 \\ = 8$