How do you solve #x^2 - 17x + 72 =0# using the quadratic formula?

1 Answer
Feb 26, 2016

Solution is #x=9# or #x=8#

Explanation:

For equation #ax^2+bx+c=0#, the solution given by quadratic formula is #(-b+-sqrt(b^2-4ac))/(2a)#.

To solve #x^2−17x+72=0#, we know that #a=1#, #b=-17# and #c=72#

Hence, solution is given by #(-(-17)+-sqrt((-17)^2-4*1*72))/(2*1)# or

#(17+-sqrt(289-288))/2# or #(17+-1)/2# or #(17+1)/2# and #(17-1)/2#

Hence, solution is #x=9# or #x=8#