SOLUTION: Find the largest value of x such that 3x^2 + 17x + 15 = 2x^2 + 21x + 12

SOLUTION: Find the largest value of x such that 3x^2 + 17x + 15 = 2x^2 + 21x + 12 - 5x^2 + 17x + 34.

Question 1209215: Find the largest value of x such that 3x^2 + 17x + 15 = 2x^2 + 21x + 12 - 5x^2 + 17x + 34.
Answer by ikleyn(52790) (Show Source): You can put this solution on YOUR website!
.
Find the largest value of x such that 3x^2 + 17x + 15 = 2x^2 + 21x + 12 - 5x^2 + 17x + 34.
~~~~~~~~~~~~~~~~~~~~~~~~

Collect all the terms of the equation in its left side

    3x^2 + 17x + 15 - 2x^2 - 21x - 12 + 5x^2 - 17x - 34 = 0.


Group like terms

    (3x^2 - 2x^2 + 5x^2) + (17x - 21x - 17x) + (15 - 12 - 34).


Combine like terms

    6x^2 - 21x - 31 = 0.


Use the quadratic formula to find the roots

     =  = .


The greatest root is   = 4.618652413  (approximate value).


ANSWER.  The greatest root is  , or about 4.618652413  (approximate value).

Solved.

RELATED QUESTIONS
0=3x^2-17x-34 find the value of... (answered by Fombitz)

5x^2+17x-12=0 (answered by stanbon)

Find the minimum value of... (answered by nerdybill)

Factor 2x^2+17x+15 (answered by jim_thompson5910,Fombitz)

3x^2+17x+45=12 (answered by Fombitz)

-2x=11(3x-2)=17x? (answered by Alan3354)

Find the vertex of the graph of the equation y = -2x^2 + 8x - 15 - 5x^2 + 17x +... (answered by asinus)

find all horizontal asymptotes of the rational function. 1. 3x^3-17x^2+5x/x^5-2x^3... (answered by Boreal)

Find all roots of the polynomial f(x) = 2x^3 - 5x^2 - 2x + 2 - 8x^3 + 11x^2 - 17x +... (answered by CPhill)