161k views
4 votes
Solve the given equation: 2 x ( x + 3 ) − 6 ( x + 3 ) = 0 2 x ( x + 3 ) - 6 ( x + 3 ) = 0

User SyRenity
by
8.2k points

1 Answer

6 votes

Answer:

x = 3 or x = -3

Explanation:

Solve for x over the real numbers:

2 x (x + 3) - 6 (x + 3) = 0

Expand out terms of the left hand side:

2 x^2 - 18 = 0

2 x^2 - 18 = 2 (x^2 - 9):

2 (x^2 - 9) = 0

Divide both sides by 2:

x^2 - 9 = 0

x = (0 ± sqrt(0^2 - 4 (-9)))/2 = ( ± sqrt(36))/2:

x = sqrt(36)/2 or x = (-sqrt(36))/2

sqrt(36) = sqrt(4×9) = sqrt(2^2×3^2) = 2×3 = 6:

x = 6/2 or x = (-6)/2

6/2 = 3:

x = 3 or x = (-6)/2

(-6)/2 = -3:

Answer: x = 3 or x = -3

User Bert Goethals
by
7.9k points

No related questions found

Welcome to QAmmunity.org, where you can ask questions and receive answers from other members of our community.

9.4m questions

12.2m answers

Categories