SOLUTION: y=2x=4 x-4y=-7 solve each linear equations if possible.

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Question 19498: y=2x=4
x-4y=-7
solve each linear equations if possible.
Answer by MelanieBCC(40) About Me  (Show Source):
You can put this solution on YOUR website!
On your first equation there are 2 equal signs. I'm going to solve this as if it is y=2x-4. I'll do this step by step so that you can apply the information if the equation is supposed to be something else.
There are 2 methods to solve a system of linear equations, substitution and elimination. For this system, substitution is easiest, because we know that y equals 2x-4. Since this information came from the first equation, we use it in the second by substituting all y values in the second equation with 2x-4 to get:
x-4%282x-4%29=-7 and then solving for x
x-4%282x-4%29=-7 becomes x-8x-7=-7 which becomes -7x=0 which becomes x=0
Go back to the first equation and substitute 0 for all values of x. This gives you y=2%280%29-4 which becomes y=-4
I hope this helps!