Algebra
LINEAR EQUATIONS
Step 3.
Check the root by substituting it for the unknowns
in the original equation.
Example 1:
Solve the equation 3x + 7 = 13.
Solution:
Step 1.
Using Axiom 2, subtract 7 from both sides of the
equation.
3x + 7 - 7 = 13 - 7
3x = 6
Step 2.
Using Axiom 4, divide both sides of the equation by
3.
3x
3
6
3
x = 2
Step 3.
Check the root.
3(2) + 7 = 6 + 7 = 13
The root checks.
Example 2:
Solve the equation 2x + 9 = 3(x + 4).
Solution:
Step 1.
Using Axiom 2, subtract 3x and 9 from both sides
of the equation.
2x + 9 = 3(x + 4)
2x + 9 - 3x - 9 = 3x + 12 - 3x - 9
-x = 3
Step 2.
Using Axiom 4, divide both sides of the equation by
-1.
x
1
3
1
x = -3
Rev. 0
Page 7
MA-02
