Solve the following by factorisation: 8x2-22x-21=0.
Step: Solve the given equation by factorisation
⇒8x2-22x-21=0⇒8x2-28x+6x-21=0⇒4x(2x-7)+3(2x-7)=0⇒(4x+3)(2x-7)=0⇒4x+3=0or2x-7=0⇒x=-34orx=72
Thus, the roots of the equation from factorisation are -34 and 72.
Solve the following quadratics 8x2−9x+3=0