Question

Andre and Elena are solving this system of equations:

equation 1: y=3x
equation 2: y=9x - 30
Andre's first step is to write: 3x = 9x – 30
Elena's first step is to create a new system:
new equation 1: 3y = 9x
new equation 2: y= 9x - 30
Do you agree with either first step? Explain your
reasoning.

Answer 1

Andre's step is incorrect while Elena's step is correct in solving the system of equations.

Step-by-step explanation:

Andre and Elena are both attempting to solve a system of equations. Andre's first step is to write the equation '3x = 9x - 30', while Elena's first step is to create a new system with equations '3y = 9x' and 'y = 9x - 30'.

Andre's step is incorrect because he is writing the equation by equating the x-terms on both sides of the equation, which ignores the y-terms present in the original equations.

Elena's step is correct because she is creating a new system of equations that properly takes into account the y-terms present in the original equations.