For the following system, if you isolated x in the first equation to use the substitution method, what expression would you substitute into the second equation? -x - 2y = -4 3x + y = 12
a. -2y - 4
b. 2y - 4
c. 2y + 4
d. -2y + 4

When a whole number is multiplied by 104, how does the placement of the decimal point change? a. it moves ten places to the right. b. it moves four places to the left. c. it moves ten places to the left. d. it moves four places to the right.