How do you solve using the quadratic formula #x^2-5x-14=0#?
1 Answer
May 16, 2015
D = d^2 = 25 + 56 = 81 -> d = +-9
x = 5/2 + 9/2 = 14/2 = 7
x = 5/2 - 9/2 = -4/2 = -2
There is another way that is faster. (new AC Method)
Find 2 numbers knowing product (-14) and sum (7). Compose factor pairs of (-14): (-1, 14)(-2, 7). This last sum is 5 = -b. Then the 2 real roots are: -2 and 7
