Solve this equation using the quadratic formula.  3x^2 -5 = -8x -10

2 Answers

embizze's profile pic

embizze | High School Teacher | (Level 2) Educator Emeritus

Posted on

Solve `3x^2-5=-8x-10` using the quadratic formula:

The quadratic formula is : if `ax^2+bx+c=0 "then" x=(-b+-sqrt(b^2-4ac))/(2a)`

We must rewrite in standard form:

`3x^2+8x+5=0` Now a=3,b=8, and c=5 so:







The solutions are `x=-1,-5/3`


You could factor:

`3x^2+8x+5=(3x+5)(x+1)` and find the roots that way also.

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oldnick | (Level 1) Valedictorian

Posted on






`3x+5=0 rArr x=-5/3`

`x+1=0 rArr x=-1`

So solutions are  `x_1=-1``x_2=-5/3`