Chapter 6.4, Problem 21PPE

To determine

To decide: The method which will be best suitable to solve the given system of linear equations.

Answer to Problem 21PPE

Graphing method

Explanation of Solution

Given information:

The equations $4s-3t=8$ and $t=-2s-1$

Concept Used:

• Substitution method is best suitable when either ofvariables can be expressed easily in terms of other variable using one equation.
• Elimination method is best suitable when any one of variable term can be cancelled out easily by simple addition or subtraction of equations.
• Graphing is best when the system of equations is complex to solve and when both of above two methods fails will result in a complicated process.

In the given system of linear equations a value of t in terms of s is already given in equation $t=-2s-1$ . However substitution this value in equation $4s-3t=8$ will further lead to complicated process.

Also using elimination method will be complicated process as it’s not easy to cancel out any of terms.

Therefore it is best to use the graphing method to solve these set of equations.