Answer:
x=3
Y=−4
Explanation:
Y=−7/3x+3
Y=−1/3x−3
Consider the first equation. Add
3
7
x to both sides.
Y+
3
7
x=3
Consider the second equation. Add
3
1
x to both sides.
Y+
3
1
x=−3
To solve a pair of equations using substitution, first solve one of the equations for one of the variables. Then substitute the result for that variable in the other equation.
Y+
3
7
x=3,Y+
3
1
x=−3
Choose one of the equations and solve it for Y by isolating Y on the left hand side of the equal sign.
Y+
3
7
x=3
Subtract
3
7x
from both sides of the equation.
Y=−
3
7
x+3
Substitute −
3
7x
+3 for Y in the other equation, Y+
3
1
x=−3.
−
3
7
x+3+
3
1
x=−3
Add −
3
7x
to
3
x
.
−2x+3=−3
Subtract 3 from both sides of the equation.
−2x=−6
Divide both sides by −2.
x=3
Substitute 3 for x in Y=−
3
7
x+3. Because the resulting equation contains only one variable, you can solve for Y directly.
Y=−
3
7
×3+3
Multiply −
3
7
times 3.
Y=−7+3
Add 3 to −7.
Y=−4
The system is now solved.
Y=−4,x=3