Solve 3x(x+2)=-18: Is -1+or-the square root of 5 Correct?

  • Thread starter Thread starter aisha
  • Start date Start date
Click For Summary
SUMMARY

The equation 3x(x+2) = -18 can be solved using both the completing the square method and the quadratic formula. The correct solutions are x = -1 ± √5. The discussion confirms that the right-hand side of the equation is indeed -18, clarifying any confusion regarding the sign. Both methods yield the same results, affirming the accuracy of the solutions provided.

PREREQUISITES
  • Understanding of quadratic equations
  • Familiarity with the quadratic formula
  • Knowledge of completing the square technique
  • Basic algebraic manipulation skills
NEXT STEPS
  • Study the quadratic formula in detail
  • Practice completing the square with various quadratic equations
  • Explore the implications of different right-hand side values in quadratic equations
  • Learn about graphing quadratic functions to visualize solutions
USEFUL FOR

Students learning algebra, educators teaching quadratic equations, and anyone looking to improve their problem-solving skills in mathematics.

aisha
Messages
584
Reaction score
0
:smile: Solve 3x(x+2)=-18 by completing square and quadratic formula. I did both methods and got -1+or-the square root of 5 i
Can someone just tell me if this is correct?
 
Last edited:
Physics news on Phys.org
Is that +18 or -18 ?

You're right if it's +18 and the RHS of the equation is " = 0 ".
 
Last edited:
Yes sorry the equation was =-18
Thanks for checking :smile:
 

Similar threads

Why is the square root of x^2 = |x|?
  • · Replies 14 ·
Replies
14
Views
2K
Is Removing c from the Square Root in This Equation Correct?
  • · Replies 25 ·
Replies
25
Views
2K
Calculating Masses Using Gravitational Force Equations
  • · Replies 5 ·
Replies
5
Views
1K
Root-mean squared values and a.c. emf
  • · Replies 5 ·
Replies
5
Views
3K
How to find the equilibrium position of three masses (two of them fixed)?
  • · Replies 4 ·
Replies
4
Views
2K
Time period of SHM & Energy conservation in pulley-spring-block system
  • · Replies 24 ·
Replies
24
Views
4K
Analyse motion of an oscillator: x(t)=0.2cos(12*pi*t)
  • · Replies 5 ·
Replies
5
Views
2K
Pressure question: Weight of a car calculated from tyre contact patch area
  • · Replies 3 ·
Replies
3
Views
1K
Solve using complete the square vs. quadratic formula
  • · Replies 11 ·
Replies
11
Views
3K
Is it possible to solve relative velocity problems without sine law?
  • · Replies 25 ·
Replies
25
Views
2K