How do you factor completely # 4x^2 - 28x +40#?

2 Answers
Apr 8, 2016

#4x^2-28x+40=4(x-5)(x-2)#

Explanation:

#4x^2-28x+40=4color(red)((x^2-7x+10))#

#color(red)(x^2-7x+10)=(x-5)(x-2)#

#4x^2-28x+40=4(x-5)(x-2)#

Apr 8, 2016

#4x^2-28x+40= color(green)(4(x-5)(x-2))#

Explanation:

Given
#color(white)("XXX")4x^2-28x+40#
Extract the simple constant factor of #4#
#color(white)("XXX")=4(x^2-7x+10)#factor the second part by inspection or use of the quadratic formula to get
#color(white)("XXX")=4(x-2)(x-5)#