Chapter 6.4, Problem 18MCQ

To determine

Totell:The method should be used to solve given system of equations explaining the answer.

Answer to Problem 18MCQ

The method of substitution should be used.

Explanation of Solution

Given information:

The system of equations is

  $2y+7x=3$ , $y-7x=9$ ,

One can use method of graphing, substitution, and elimination.

Conceptused:

In method of elimination the adding or subtracting one equation to or from, we obtain an equation in single variable that can be solved quickly.

The system of equations is

  $2y+7x=3$ ...........(1)

  $y-7x=9$ ............ (2)

For solving given system of equations we use method of elimination.

The reason is that adding equations (1) and (2) we get directly an equation in single variabley no reshuffling or arrangement of terms of any equation is required, and the so obtained equation in single variable y can be solved quickly.

Conclusion:

The method of elimination should be used.