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SOLVING
EQUATIONS WITH ONE VARIABLE
A) Simple Equations
Three steps to solve a simple equation:
1. Move all
terms containing the unknow to the left side of the equation.
2. Collect
like terms.
3. Divide
by the coefficient of the unknown to get the answer.
Example
1: Solve
5x - 12 = 3x + 4
Solution:
5x
-3x = 4 + 12
2x
= 16
x = 8
Answer:
x = 8
B)
Equation
with Fractions
Multiply
both member of the equation for the Least Common Multiple among
all denominators.
Example:
Solve
Multiplying
by the LCD=30 we get:

C)
Equation with Parenthesis
- Remove
the parenthesis performing the corresponding operations and
proceed as in 1).
Example:
Solve 3 (2x 3) = 6 + 3(x + 5)
3
2x + 3 = 6 + 3x + 15
-2x
3x = 6 + 15 6
-5x
= 15
x
= -3
D) With Multiple Parenthesis
Remove parenthesis
(using FOIL when applicable). Use auxiliary parenthesis for
partial results., finally proceeds as in 3)
Example: Solve
5 +(2x+1)(x+3) = 3x2 (x+3)(x+2)
5
+ (2x2 + 6x +x +3) = 3x2 (x2
+2x+3x+6)
5
+ 2x2 + 6x +x +3 = 3x2 x2
-2x-3x-6
2x2
+ 7x + 8 = 2x2 -5x-6
7x
+ 5x = -6-8
12x
= -14
x
= -7/6
E)
Fractional Type
Multiply
the equation by the LCD Example: Solve

Multiplying
by the LCD (x-3)(x+2) , we get

It's easy
to check that x=4 satisfies the equation.
F) Equation with Radical
Isolate
the radical and then power both members of new equation to
eliminate the radical.
Do not forget
to check your possible solutions!
Example: Solve:
Isolating
the radical we get:

Checking
x=5, we get

So x=5 is
the solution.
F)
Equation with no Solution
Example: Solve
Isolating
the radical we get:
 
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for more examples
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