Solving quadratics by completing the square k2 6k 51 4Sol

Solving quadratics by completing the square k^2 + 6k - 51 = 4

Solution

k²+6k-51=4;
k² +6k +a = 55+a
k²+6k+ 9 = 55+9
(k+3) ²= 64 ;
(k+3)²= 8²;
k+3= sqrt(64)
k+3 = +8 or -8;
k+3=-8 means k=-11
k+3=8 means k=5

Thus the solution for k is k=5 or k=-11