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4 votes
Simplify:

9 – 3 x 2 + 4

1 Answer

4 votes

Answer:

2

:

5STEP

2

:

Trying to factor as a Difference of Squares:

2.1 Factoring: 5-3x2

Theory : A difference of two perfect squares, A2 - B2 can be factored into (A+B) • (A-B)

Proof : (A+B) • (A-B) =

A2 - AB + BA - B2 =

A2 - AB + AB - B2 =

A2 - B2

Note : AB = BA is the commutative property of multiplication.

Note : - AB + AB equals zero and is therefore eliminated from the expression.

Check : 5 is not a square !!

Ruling : Binomial can not be factored as the

difference of two perfect squares

Equation at the end of step

2

:

5 - 3x2 = 0

STEP

3

:

Solving a Single Variable Equation:

3.1 Solve : -3x2+5 = 0

Subtract 5 from both sides of the equation :

-3x2 = -5

Multiply both sides of the equation by (-1) : 3x2 = 5

Divide both sides of the equation by 3:

x2 = 5/3 = 1.667

When two things are equal, their square roots are equal. Taking the square root of the two sides of the equation we get:

x = ± √ 5/3

The equation has two real solutions

These solutions are x = ±√ 1.667 = ± 1.29099

Two solutions were found :

x = ±√ 1.667 = ± 1.29099

User Surga
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