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Have to be done by midnight and i have no idea what i am doing

Have to be done by midnight and i have no idea what i am doing-example-1

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Answer:


Explanation:

These seem to be simultaneous equations. I'll solve the first one and show you the process of how its done.

There are two methods to solve simultaneous equations, either by substitution or elimination, the elimination method is generally easier so I will demonstrate that for now.

1. 5x + y = 9 and 10x -7y = -18

To use elimination, you need a term, either the x or y term to cancel leaving you with only one variable to solve for. This is done by multiplying the equation by a number so that when you add the equations together the variable will cancel.

So for 1 if I wanted x to cancel:

-2 (5x + y = 9) I would multiply -2 to that equation so the -10x and 10x would cancel when I add them:

By multiplying by -2 I get

-10x - 2y = -18 , Now add this to the other equation:

10x - 7y = -18

-9y = -36 ; Notice how the x terms canceled

Now divide by -9 and we get y = 4

Now to get the value for x, plug y = 4 into either one of the equations, it doesnt matter which one you pick you will get the same value.

Ill pick the first one

So... 5x + 4 = 9

Subtract 4

5x = 5

Divide by 5

x = 1

So the answer is y = 4 and x = 1

If you'd like me to do more let me know but I hope this helped!

User ArjunShankar
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