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2 votes
3x (x - 2) = x^2 - 4

User Montycarlo
by
5.3k points

1 Answer

3 votes

Answer:

x = 1, x = 2

Explanation:

Given

3x(x - 2) = x² - 4 ← distribute parenthesis on left side

3x² - 6x = x² - 4 ( subtract x² - 4 from both sides )

2x² - 6x + 4 = 0 ( divide through by 2

x² - 3x + 2 = 0 ← in standard form

Consider the factors of the constant term (+ 2) which sum to give the coefficient of the x- term (- 3)

The factors are - 1 and - 2 , since

- 1 × - 2 = + 2 and - 1 - 2 = - 3 , then

(x - 1)(x - 2) = 0 ← in factored form

Equate each factor to zero and solve for x

x - 1 = 0 ⇒ x = 1

x - 2 = 0 ⇒ x = 2

User Jubbles
by
5.1k points
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