Question

5X + 4Y = 6 , 2X + 4Y = 12 ​

Answer 1

Answer:

this is the first one

x=-2

y=4

second

x=2

y=2

Step-by-step explanation:

1)

5×(-2)+4×4

-10+16

6

2)

2×2+4×2

4+8

12

Answer 2

Question -

Solve the following pair of equations by substitution method -

5x+4y=6

2x+4y=12

Solution -

Given equations,

5x+4y=6.......1)

And,

2x+4y=12

4y= 12-2x.......2)

By substituting the value of 4y in equation 1) we will get -

$5x + 4y = 6$

$5x + 12 - 2x = 6$

$3x + 12 = 6$

$3x = 6 - 12$

$3x = - 6$

$x = \frac{ - 6}{3}$

$x = - 2$

Now substituting the value of x in equation 2) we will get -

$4y = 12 - 2x$

$4y = 12 - 2( - 2)$

$4y = 12 + 4$

$4y = 16$

$y = \frac{16}{4}$

$y = 4$

Verification -

5x+4y = 6

Putting the value of x and y

5(-2) + 4×4=6

-10+16=6

6=6

Also,

2x+4y=12

2(-2)+4×4=12

-4+16=12

12=12

L.H.S =R.H.S

Hence, verified

Therefore the value of x is - 2 and y is 4