SOLUTION: If possible solve the system of equations. Use any method. If there is not a unique solution state a reason why
3x-9y=3
-15x+45y=-15
thanks!!
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Polynomials-and-rational-expressions
-> SOLUTION: If possible solve the system of equations. Use any method. If there is not a unique solution state a reason why
3x-9y=3
-15x+45y=-15
thanks!!
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Question 729791: If possible solve the system of equations. Use any method. If there is not a unique solution state a reason why
3x-9y=3
-15x+45y=-15
thanks!! Answer by lenny460(1073) (Show Source):
You can put this solution on YOUR website! If possible solve the system of equations. Use any method. If there is not a unique solution state a reason why
3x - 9y = 3
-15x + 45y = -15
thanks!!
The above system of equation can be
solved by substitution.
3x - 9y = 3 (Equation 1)
-15x + 45y = -15 (Equation 2)
We first take Equation 1
3x - 9y = 3
Add 9y to each side of the equation.
3x - 9y + 9y = 3 + 9y
3x = 3 + 9y
Divide each item above by 3:
x = 1 + 3y (Equation 3)
Substitute Equation 3 into Equation 2.
-15x + 45y = -15 (Equation 2)
-15(1 + 3y) + 45y = -15
-15 - 45y + 45y = -15
Combine like terms:
-45y + 45y = 0
Therefore:
-15 = -15
Divide each side by -15
x = 1
Substitute x = 1 into Equation 1
3x - 9y = 3
3(1) - 9y = 3
3 - 9y = 3
Add 9y to each side of the equation.
3 - 9y + 9y = 3 + 9y
3 = 3 + 9y
Subtract 3 from each side of the equation.
3 - 3 = 3 + 9y - 3
0 = 9y or
9y = 0
Therefore:
y = 0
