4.
Which two steps should be used first in solving the system of equations by substitution?
A:Substitute 9 for y in the first equation and then solve the other equation for x.
B:Solve the second equation for y and then substitute this value into the first equation.
C:Subtract the terms in the second equation from the first equation and then solve for y
D:Multiply the first equation by 4 and the second equation by 2.

4 Which two steps should be used first in solving the system of equations by substitution ASubstitute 9 for y in the first equation and then solve the other equ class=