Question

which method might be preferred if the coefficients of one variable are already opposites?
a. graphical
b. substitution
c. elimination
d. numerical

which system is best solved by the substitution method?
a. systems where one equation is easily solvable for one variable
b. systems with high coefficients
c. systems that involve quadratic equations
d. systems where both equations are in standard form

Explanation:

Step1: Match method to coefficient condition

When coefficients of one variable are opposites, adding the equations eliminates that variable directly, making elimination the ideal method.

Step2: Match system to substitution method

Substitution works best when you can easily isolate one variable in one equation and substitute it into the other equation, which describes the scenario in option a.

Answer:

1. c. Elimination
2. a. Systems where one equation is easily solvable for one variable