Question

Quadratic formula 9x²-6x-11=0

Answer 1

`9x ^(2)-6x-11=0 \\ \\ a=9 , \ b=-6, \ c = -11 \\ \\ \Delta = b^(2)-4ac = (-6)^(2)-4*9* (-11)= 36+396 = 432\\ \\√(\Delta )=√(432)= √(144*3)=12√(3)\\ \\x_(1)=(-b-√(\Delta ))/(2a) =(6-12√(3))/(2*9)=( 6(2-2√(3)))/(18)= ( 2-2√(3) )/(3) \\ \\x_(2)=(-b+√(\Delta ))/(2a) =(6+12√(3))/(2*9)=( 6(2+2√(3)))/(18)= ( 2+2√(3) )/(3)`