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X + y = 1 and 5x - 4y = -7 How would I solve by substitution?

User Bajaj
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1 Answer

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Final answer:

To solve the system of equations x + y = 1 and 5x - 4y = -7 by substitution, solve one equation for one variable and substitute it into the other equation. The solution is x = -1/3 and y = 4/3.

Step-by-step explanation:

To solve the system of equations x + y = 1 and 5x - 4y = -7 by substitution, we can solve one of the equations for one variable and substitute it into the other equation. Let's solve the first equation for x:

x = 1 - y

Now substitute this value of x into the second equation:

5(1 - y) - 4y = -7

5 - 5y - 4y = -7

-9y = -12

y = 4/3

Substitute this value of y back into x = 1 - y:

x = 1 - (4/3)

x = -1/3

So the solution to the system of equations is x = -1/3 and y = 4/3.

User Jayanta
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