How do you factor the quadratic expression completely? 2x^2 - 13x + 20

2 Answers
Jun 10, 2018

(x-4)(2x-5)

Explanation:

2x^{2}-13x+20

Factors of 20 * 2 which add up to -13 are -5 and -8

so you can replace -13 with -5 and -8 such that:

2x^{2}-5x-8x+20
which goes to:
x(2x-5)-4(2x-5)

Take the expressions not in the brackets together to get:
(x-4)(2x-5)

Jun 10, 2018

(x-4)(x-5/2)

Explanation:

2x^2-13x+20

The simplest way to do this is using the quadratic equation:

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

Where,
a=2
b=-13
c=20

x=(-(-13)+-sqrt((-13)^2-4*2*20))/(2*2)

x=((13)+-sqrt(169-160))/(4)
x=((13)+-sqrt(9))/(4)
x=4 and x=5/2

x-4=0
x-5/2=0

Therefore,

2x^2-13x+20= (x-4)(x-5/2)