Question

2x+4y=12

Answer 1

2x+4y=12 
y=1/4x-3

can be re-written as

2x + 4y = 12                   4y+2x = 12
4y= x - 12             or     -4y -x = 12
                                      ------------------

Adding, we get                     x = 24.

From the given equation  y=1/4x-3 (better written as y = (1/4)x - 3), we
get y = (1/4)(24) - 3, or 6 - 3, or 3.

The solution is thus (24, 3).

Here I used the "addition-subtraction method" to solve this system of equations.

Answer 2

Answer: The solution of the system of the equation is, (8,-1)

Step-by-step explanation:

Using substitution method

$2x+4y=12$      .......... (1)

$y=\frac{1}{4}x-3$      ......... (2)

Now we are putting equation (2) into equation (1), we get the value of 'x'

$2x+4(\frac{1}{4}x-3)=12$

$2x+\frac{4}{4}x-4\times 3=12$

$2x-x=12+12$

$3x=24$

$x=8$

Now put the value of 'x' in equation (2), we get the value of 'y'

$y=\frac{1}{4}x-3$

$y=\frac{1}{4}\times 8-3$

$y=2-3$

$y=-1$

Hence, the correct option is, (8,-1)