Final answer:
To solve the system of equations by substitution, solve one equation for one variable and substitute that expression into the other equation. The solution to the given system of equations is x = 6 and y = -21.
Step-by-step explanation:
To solve the system of equations by substitution, we need to first solve one equation for one variable and then substitute that expression into the other equation. Let's solve the equation 7x + 2y = -19 for y:
2y = -7x - 19
y = (-7/2)x - 19/2
Now, we substitute this expression for y into the other given equation:
-x + 27 = 21
-x = -6
x = 6
Substituting this value of x back into the expression for y, we get:
y = (-7/2)(6) - 19/2
y = -21
Therefore, the solution to the system of equations is x = 6 and y = -21.
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