Question

Solve the equation by completing the square. -9n^2+79+=-18n

Answer 1

Hello,
-9n²+79=-18n
==>9n²-18n-79=0
==>9(n²-2n+1-1)-79=0
==>9(n-1)²-88=0
==>[3(n-1)-2√22][3(n-1)+2√22]=0
==>3(n-1)=2√22 or 3(n-1)=-2√22
==>n-1=2/3*√22 or n-1=-2/3*√22
==>n=1+2/3*√22 or n=1-2/3*√22