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Solve the system of equations by using substitution.
x+8y=-2
x-3y=20

User Volatility
by
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1 Answer

6 votes

Answer:

(14, -2)

Explanation:

To solve by using substitution, begin by solving for a variable in the first equation. Let's solve for x:


x+8y=-2\\x=-2-8y

Now we know what x equals. Let's substitute this into the second equation:


x-3y=20\\(-2-8y)-3y=20

We can then simplify:


-2-8y-3y=20 Given equation


-2-11y=20 Combine y terms


-11y=22 Add 2


y=-2 Divide by -11

So, we now know the value of y = -2.

To find the value of X, we can substitute the value of Y into one of the equations. Let's use the first one:


x+8y=-2


x+8(-2)=-2 Substitute for y


x-16=-2 Distribute 8


x=14 Add 16

So, we now know the value of x = 14.

Therefore, we know a solution to the system of equations is (14, -2).

User Rindra
by
5.2k points