Learn on PengienVision, Mathematics, Grade 6Chapter 4: Represent and Solve Equations and Inequalities

Lesson 1: Understand Equations and Solutions

In this Grade 6 lesson from enVision Mathematics, students learn to identify equations and their solutions by determining whether a given value for a variable makes an equation true. Using substitution, students evaluate expressions on both sides of an equation and check for equality across real-world contexts like gift cards and marbles. The lesson aligns with Common Core standard 6.EE.B.5 and builds foundational skills for solving equations in Chapter 4.

Section 1

Equation and Solution

Property

An equation is a statement that two expressions are equal. It may involve one or more variables. A value of the variable that makes an equation true is called a solution of the equation, and the process of finding this value is called solving the equation.

Examples

  • The statement x+5=12x + 5 = 12 is an equation. The value x=7x=7 is a solution because 7+5=127 + 5 = 12 is a true statement.
  • To check if y=3y=3 is a solution to 8y=248y = 24, we substitute it in: 8(3)=248(3) = 24. This is true, so y=3y=3 is a solution.
  • Is z=10z=10 a solution for z4=5z - 4 = 5? We check: 104=610 - 4 = 6. Since 66 is not equal to 55, z=10z=10 is not a solution.

Explanation

Think of an equation as a perfectly balanced scale. A solution is the specific value for the variable that keeps the scale level. Finding that value is what we call solving the equation.

Section 2

Verify a solution of an equation

Property

A solution of an equation is a value of a variable that makes a true statement when substituted into the equation.

To determine whether a number is a solution to an equation.
Step 1. Substitute the number in for the variable in the equation.
Step 2. Simplify the expressions on both sides of the equation.
Step 3. Determine whether the resulting equation is true. If it is true, the number is a solution. If it is not true, the number is not a solution.

Examples

  • Is y=4y=4 a solution to 5y3=175y - 3 = 17? Substitute y=4y=4: 5(4)3=203=175(4) - 3 = 20 - 3 = 17. Since 17=1717=17, yes, it is a solution.
  • Is x=3x=3 a solution to 2x+8=x+42x + 8 = x+4? Substitute x=3x=3: 2(3)+8=142(3) + 8 = 14 and 3+4=73+4=7. Since 14714 \neq 7, it is not a solution.
  • Is a=12a = \frac{1}{2} a solution to 8a1=38a - 1 = 3? Substitute a=12a=\frac{1}{2}: 8(12)1=41=38(\frac{1}{2}) - 1 = 4 - 1 = 3. Since 3=33=3, yes, it is a solution.

Lesson overview

Expand to review the lesson summary and core properties.

Expand

Section 1

Equation and Solution

Property

An equation is a statement that two expressions are equal. It may involve one or more variables. A value of the variable that makes an equation true is called a solution of the equation, and the process of finding this value is called solving the equation.

Examples

  • The statement x+5=12x + 5 = 12 is an equation. The value x=7x=7 is a solution because 7+5=127 + 5 = 12 is a true statement.
  • To check if y=3y=3 is a solution to 8y=248y = 24, we substitute it in: 8(3)=248(3) = 24. This is true, so y=3y=3 is a solution.
  • Is z=10z=10 a solution for z4=5z - 4 = 5? We check: 104=610 - 4 = 6. Since 66 is not equal to 55, z=10z=10 is not a solution.

Explanation

Think of an equation as a perfectly balanced scale. A solution is the specific value for the variable that keeps the scale level. Finding that value is what we call solving the equation.

Section 2

Verify a solution of an equation

Property

A solution of an equation is a value of a variable that makes a true statement when substituted into the equation.

To determine whether a number is a solution to an equation.
Step 1. Substitute the number in for the variable in the equation.
Step 2. Simplify the expressions on both sides of the equation.
Step 3. Determine whether the resulting equation is true. If it is true, the number is a solution. If it is not true, the number is not a solution.

Examples

  • Is y=4y=4 a solution to 5y3=175y - 3 = 17? Substitute y=4y=4: 5(4)3=203=175(4) - 3 = 20 - 3 = 17. Since 17=1717=17, yes, it is a solution.
  • Is x=3x=3 a solution to 2x+8=x+42x + 8 = x+4? Substitute x=3x=3: 2(3)+8=142(3) + 8 = 14 and 3+4=73+4=7. Since 14714 \neq 7, it is not a solution.
  • Is a=12a = \frac{1}{2} a solution to 8a1=38a - 1 = 3? Substitute a=12a=\frac{1}{2}: 8(12)1=41=38(\frac{1}{2}) - 1 = 4 - 1 = 3. Since 3=33=3, yes, it is a solution.