SOLUTION: Solve by substitution x + 5y = 0 -2x -4y = 6 Got a test and I still can't grasp this. Any help is appreciated.

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Question 91616: Solve by substitution x + 5y = 0
-2x -4y = 6
Got a test and I still can't grasp this. Any help is appreciated.
Found 2 solutions by stanbon, praseenakos@yahoo.com:
Answer by stanbon(75887) (Show Source):
You can put this solution on YOUR website!
Solve by substitution
x + 5y = 0
-2x -4y = 6
----------------
Solve an equation for one of the variables.
For example, solve the 1st equation for "x":
x = -5y
----------
Substitute that value of x into the 2nd equation:
-2(-5y)-4y=6
Sove for y:
10y-4y=6
6y=6
y=1
---------------
Substitute that value of y into the equation x=-5y
x=-5*1 = -5
-----------------
Solution for the system of equations: x=-5, y=1
============================
Cheers,
Stan H.

Answer by praseenakos@yahoo.com(507) (Show Source):
You can put this solution on YOUR website!
Question:

Solve by substitution x + 5y = 0
-2x -4y = 6

Answer:

x + 5y = 0 ------------(1)
-2x -4y = 6 -----------(2)

(1)==> x = -5y

Plugg this value of x in the second equation.....

==> -2(-5y) -4y = 6

==> 10y - 4y = 6

==> 6y = 6

Divide both sides by 6

==>

==> y = 1

That is value of y is 1.
Now substitute the value of x in the given equation....

==> x + 5*1 = 0

==> x + 5 = 0

subtract 5 from both sides....

==> x + 5 -5 = 0 - 5

==> x = -5

That is solution is..
x = -5 and
y = 1

Hope you found the explanation useful.

Regards.

Praseena.