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Could you help me understand how to solve systems of equations and functions I do not under stand how to do it

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Step-by-step explanation

Suppose that we have the following system of equations:

(1) x + 2y = 30

(2) 3x + y = 14

The key is to isolate one variable from one equation and substitute into another in order to get the first solution:

We can first isolate x from (1) by subtracting -2y to both sides:

x + 2y - 2y = 30 - 2y

Simplifying:

x = 30 - 2y

Plugging in x = 30 - 2y into the second equation:


3(30-2y)+y=14

Applying the distributive property:


90-6y+y=14

Adding like terms:


90-5y=14

Subtracting -90 to both sides:


-5y\text{ = 14 - 90}

Dividing both sides by -5:


y=(14-90)/(-5)

Subtracting numbers:


y=(-76)/(-5)

Simplifying:


y=(76)/(5)

Now, plugging in y=76/5 into the first equation:


x+2\cdot(76)/(5)=30

Multiplying numbers:


x+(152)/(5)=30

Subtracting -152/5 to both sides:


x=30-(152)/(5)

Subtracting numbers:


x=-(2)/(5)

In conclusio, the solution to the system of equation is:

x=-2/5, y=76/5

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