Intermediate Algebra: Solve 7x^2 + 5x + 3 = 0

[Helen]

Find the imaginary solutions of the equation.
This is the problem: 7x ^ (2) + 5x +3 = 0
This is my answer:
{-5 + i sqrt(59), 5 - i sqrt (59)}
over 7--------------------7
Is this answer correct?

 

[masters]

Re: Intermediate Algebra

Almost. Your 5 in each root should be positive. And 2a is your denominator, thus 14 instead of 7.

 

[Denis]

Re: Intermediate Algebra

You mean 5's are negative, right masters?

7x^2 + 5x + 3 = 0

x = [-5 +- sqrt(5^2 - 4 * 7 * 3)] / (2 * 7)
x = [-5 +- sqrt(-59)] / 14
x = [-5 +- i * sqrt(59)] / 14

 

[masters]

Re: Intermediate Algebra

You are right. The 5s are negative.

 

[Helen]

Re: Intermediate Algebra

Masters and Denis,
Thank you both for your help. Helen