Question

3r^2-8r-28=0 Solve with quadratic formula

Answer 1

R = 8 +- sqrt(64-4*3*-28) / 6

r = 8 +- sqrt(64--336) / 6

r = 8 +- sqrt(400) / 6

r = (8 +- 20) / 6

r = 14/3 or -2

Answer 2

(8 plus of minus radical 64 + 216
divided by 
6
(8 + or - 16.73320053)/6