The question appears to be from a linear equations section of a math practice test, asking which of the given equations are linear. Equations A and B are both linear because they can be written in the standard linear form y = mx + b. Hence, the correct answer to the practice test question is D. A and B.
A linear equation is an equation between two variables that gives a straight line when plotted on a graph. It has the form y = mx + b, where m and b are constants. Looking at the provided options:
A. y = -3x is linear because it can be written in the form of y = mx + b with m = -3 and b = 0.
B. y = 0.2 + 0.74x is also linear for the same reason, with m = 0.74 and b = 0.2.
C. y=-9.4 - 2x is linear as well, with a negative slope m = -2 and an intercept b = -9.4.
Therefore, the answer to the practice test question 12.1 about linear equations is D. A and B, as both options represent linear equations.