SOLUTION: Solve the system by addition. 2x + 4y = 3 4x

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Question 80663: Solve the system by addition.
2x + 4y = 3
4x - 2y = 1
Answer by praseenakos@yahoo.com(507) (Show Source):
You can put this solution on YOUR website!
QUESTION:

Solve the system by addition.
2x + 4y = 3
4x - 2y = 1

ANSWER:

Name the given equations as follows:

2x + 4y = 3 -----------------(1)

4x - 2y = 1 -----------------(2)

Multiply the second equation with 2.

==> 2(4x - 2y ) = 2* 1

==> 2*4x - 2*2y = 2

==> 8x - 4y = 2 --------------(3)

Now consider equation (1) and (3)

2x + 4y = 3 -----------------(1)
8x - 4y = 2 -----------------(3)

Add (1) and (3)...then we have,

2x + 4y + 8x - 4y = 3 + 2

==> 2x + 8x + 4y - 4y = 5

==> 10x + 0 = 5

==> 10x = 5

Now divide both sides of the equation by 10.

==> 10x/10 = 5/10

==> x = 1/2

Now substitute the value x = 1/ in any of the given equations.

Let's take equation (1).

==> 2*(1/2)+ 4y = 3

==> 1 + 4y = 3

Subtract 1 from both sides of the expression.

==> 1 + 4y -1 = 3 - 1

==> 4y = 2

Divide both sides of the equation by 4.

==> 4y/4 = 2/4

==> y = 1/2

So the solution for the given pair of equation is

x = 1/2 and y = 1/2.

Hope you understood.

Regards.

Praseena.

SOLUTION: Solve the system by addition. 2x + 4y = 3 4x - 2y = 1