# What is the problem in substitution method?

## What is the problem in substitution method?

The method of substitution involves three steps: Solve one equation for one of the variables. Substitute (plug-in) this expression into the other equation and solve. Resubstitute the value into the original equation to find the corresponding variable.

What is the example of substitution method?

For example, if there are two equations x+y=7 and x-y=8, then from the first equation we can find that x=7-y. This is the first step of applying the substitution method.

### What are the weaknesses of using the substitution method?

1) You can take away the Variable’s so they won’t get in the way. 2) You find out you’re x and y after a few steps into the equation. 1) You could get Fraction’s and Decimal’s, which could mess up your x and y. 2) When you multiply you’re equation by the wrong number, which could mess up you’re variables.

What does solve by substitution mean?

The method of solving “by substitution” works by solving one of the equations (you choose which one) for one of the variables (you choose which one), and then plugging this back into the other equation, “substituting” for the chosen variable and solving for the other.

#### Why is substitution method better?

The substitution method is better because we believe that it is easier. Also, depending on the equation, this method involves less work. This method is the most useful system of 2 equations in 2 unknowns.

Why elimination method is the best?

The elimination method is one of the most widely used techniques for solving systems of equations. Because it enables us to eliminate or get rid of one of the variables, so we can solve a more simplified equation. Some textbooks refer to the elimination method as the addition method or the method of linear combination.

## Why do we use substitution in math?

The effective use of substitution depends on two things: first, given a situation in which variables occur, a substitution is nothing more than a change of variable; second, it is only effective if the change of variable simplifies the situation and, hopefully, enables one to solve the simplified problem.

How to solve problems using substitution?

Isolate a variable in one of the equations. (Either y = or x =).

• Substitute the isolated variable in the other equation.
• This will result in an equation with one variable. Solve the equation.
• Substitute the solution from step 3 into another equation to solve for the other variable.
• Recommended: Check the solution.
• ### How do you solve the system using substitution?

First,solve one linear equation for y in terms of x .

• Then substitute that expression for y in the other linear equation. You’ll get an equation in x .
• Solve this,and you have the x -coordinate of the intersection.
• Then plug in x to either equation to find the corresponding y -coordinate.
• How do you solve each system by substitution?

Solve the following system of equations by substitution. First, we will solve the first equation for y y. Now, we can substitute the expression x − 5 x − 5 for y y in the second equation. Now, we substitute x = 8 x = 8 into the first equation and solve for y y. Our solution is ( 8, 3) ( 8, 3).

#### How to solve by substitution steps?

Steps to Solving by Substitution: Step One→ Solve one equation for either x or y. Step Two→ Substitute the expression from step one into the 2nd equation. Step Three→ Solve the second equation for the given variable. Step Four→ Plug you solution back into the first equation.