Question

9x+3y=18; 4x-2y = 16 solve simultaneous equation
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Answer 1

Answer:

x=2.8,y=-2.4

Step-by-step explanation:

9x+3y=18 -(1)

4x-2y=16 -(2)

multiply (1) by 2 and (2) by 3

(1)==> 18x + 6y =36 -(3)

(2)==>12x-6y=48 -(4)

add both equations (3) and (4)

30x =84

x=2.8

substituting value of x in (2)

4x2.8 -2y = 16

y= (11.2-16)/2

y= -2.4

Answer 2

In context to question asked,

We have to determine the value of "x" and "y".

As per question,

We have,

$9x+3y =18 --------(1)\\4x-2y =16--------(2)$

So, for determining the value, we need to equalize the co-efficient of either "x" or "y",

So, we will multiply (1) by 2 and (2) by 3, and both the equation,

Thus we will get,

$9x+3y =18 --------(1)\\4x-2y =16--------(2)\\18x+6y =36 --------(3)\\12x-6y =48--------(4)\\Adding \: (3)\:and\:(4)\\30x = 84\\=>x = \frac{84}{30} = 2.8$

Hence, for determining the value of y we will put the value of x in (1),

$9x+3y =18\\=>3y = 18-9x\\=.y = \frac{18-9x}{3} \\=\frac{18-(9\times 2.8)}{3}\\ = \frac{18-25.2}{3} \\= \frac{-7.2}{3} = -2.4$

Hence, value of "x" will be 2.8 while the value of "y" will be - 2.4.