How do you factor and solve #x^2+2x-8=0#?
The solutions for the equation are
We can Split the Middle Term of this expression to factorise it.
In this technique, if we have to factorise an expression like
After trying out a few numbers we get
#color(blue)(x-2) =0 , color(blue)(x=2 #
#color(blue)(x + 4) =0 , color(blue)(x=-4#
2 and -4
The 2 real roots have opposite signs because ac < 0
Find 2 real roots knowing sum (-b = -2) and product (c = -8).
Factor pairs of (c = -8) --> (-2, 4)(2, -4). This last sum is (-2 = -b).
Therefor, the 2 real roots are: 2 and -4.