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Use substitution 3x + 2y=-21, x-3y=4

User Nextar
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To solve the system of equations using substitution, we will solve one equation for one variable and substitute it into the other equation.

Let's solve the second equation, x - 3y = 4, for x:

x = 3y + 4

Now we can substitute this value of x into the first equation, 3x + 2y = -21:

3(3y + 4) + 2y = -21

Simplifying this equation gives us:

9y + 12 + 2y = -21

Combining like terms, we have:

11y + 12 = -21

Subtracting 12 from both sides:

11y = -33

Dividing both sides by 11:

y = -3

Now, we can substitute this value of y back into x = 3y + 4:

x = 3(-3) + 4

Simplifying gives us:

x = -9 + 4

x = -5

Therefore, the solution to the system of equations 3x + 2y = -21 and x - 3y = 4 is x = -5 and y = -3.

User Serhat Oz
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