solve the equation 3x^2 +8x -13 = 0

3 Answers | Add Yours

justaguide's profile pic

justaguide | College Teacher | (Level 2) Distinguished Educator

Posted on

We have to solve the equation 3x^2 + 8x - 13 = 0

3x^2 + 8x - 13 = 0

x1 = [-b + sqrt (b^2 - 4ac)]/2a

=> [ -8 + sqrt(64 + 156)]/6

=> -4/3 + sqrt (220)/6

=> -4/3 + (sqrt 55) / 3

x2 = -4/3 - (sqrt 55) / 3

The solution of the equation is { -4/3 + (sqrt 55) / 3 ,  -4/3 - (sqrt 55) / 3 }

hala718's profile pic

hala718 | High School Teacher | (Level 1) Educator Emeritus

Posted on

Given the quadratic equation: 3x^2 + 8x -13 = 0

We need to find the roots of the equation .

We will use the formula to find the answer.

We know that a= 3   b= 8  and c= -13

==> x= [ -b +- sqrt(b^2-4ac)]/2a

==> x1= [ -8 + sqrt(64-4*3*-13) ]/ 2*3

            = [ -8 + sqrt(220)]/ 6

           = ( -8 + 2sqrt55]/6

              = (-4+sqrt55)/3

==> x2= ( -4-sqrt55)/3

Then the roots for the quadratic equation is:

x= { (-4+sqrt55)/3  . (-4-sqrt55)/3  }

ameripak95's profile pic

ameripak95 | Student, Grade 11 | (Level 1) Honors

Posted on

3x^2 + 8x - 13 = 0

x1 = [-b + sqrt (b^2 - 4ac)]/2a

=> [ -8 + sqrt(64 + 156)]/6

=> -4/3 + sqrt (220)/6

=> -4/3 + (sqrt 55) / 3

x2 = -4/3 - (sqrt 55) / 3

The solution of the equation is { -4/3 + (sqrt 55) / 3 ,  -4/3 - (sqrt 55) / 3 }


 

We’ve answered 318,993 questions. We can answer yours, too.

Ask a question