DommYoung
contestada

Which expression represents the factored form of 6x^2 - 13x - 5?
a) (2x + 5) (3x - 1)
b) (2x- 5) (3x + 1)
c) (6x-5) (x + 1)
d) 6x + 1) (x - 5)

Respuesta :

apologiabiology
to FL and add
multiply first terms and multiply last terms and add and see if we get the middle term
example
(x+2)(2x-3)=2x^2+x-6x
2*2x+x*-3=4x-3x=x=middle term so



a. (2x+5)(3x-1)
2x*-1+5*3x=-2x+15x=13x, no we want -13x

b. (2x-5)(3x+1)
2x*1+-5*3x=2x-15x=-13x correct



answer is B
frika

For the quadratic trinomial [tex] ax^2+bx+c [/tex] the following formula

[tex] ax^2+bx+c=a(x-x_1)(x-x_2) [/tex], where [tex] x_1, x_2 [/tex] are trinomial roots, holds.

1. For trinomial [tex] 6x^2 - 13x - 5 [/tex] find the roots:

[tex] D=(-13)^2-4\cdot (-5)\cdot 6=169+120=289,\ \sqrt{D}=17,\\ \\
x_1=\dfrac{13-17}{2\cdot 6} = -\dfrac{4}{12} =-\dfrac{1}{3} ,\\ \\
x_2=\dfrac{13+17}{2\cdot 6} = \dfrac{30}{12} =\dfrac{5}{2} [/tex].

2. The factoring form is

[tex] 6x^2-13x-5=6\left(x+\dfrac{1}{3}\right)\left(x-\dfrac{5}{2}\right) =(3x+1)(2x-5) [/tex]

Answer: correct option is B.

Q&A Education