How do you solve #30x^2-5x=60#?

1 Answer
May 21, 2017

Answer:

#x=3/2, #
#x=-4/3#

Explanation:

The contributor below solved it by factoring, here I'll solve it using my favourite method for quadratic equations : The Quadratic Formula.

So, like the contributor above, divide the entire equation by 5.
#6x^2-x=12#
Subtract 12 from both sides.
#6x^2-x-12#
Here is where we deviate from the factoring method : We take #a=6, b=-1, c=-12#
And substitute it into the quadratic formula which is : #(-b+-sqrt(b^2-4ac))/(2a)#
You'll get :
#(-(-1)+-sqrt((-1)^2-4*6*-12))/(2*6)#
Simplify
#(1+sqrt(1+288))/12#

#(1+sqrt(289))/12#

#1/12+sqrt(289)/12, 1/12-sqrt(289)/12#

#1/12+17/12, 1/12-17/12#

#18/12, -16/12#

#3/2, -4/3#