Question

X squared minus 9 X upon X + 3 equal to 4 by 7

Answer 1

(x²-9x)/x+3 =4/7

(x²-9x)7=4(x+3)

7x²-63x=4x+12

7x²-67x-12=0

compare this equation by quadratic equation ax²+bx+c=0 whose roots are given as follows:

x= (-b+√(b²-4ac)/2a ,  (-b-√(b²-4ac)/2a

so, x= {67+√(67²+4*7*12)}/2*7  ,  {67-√(67²+4*7*12)}/2*7  

x=9.74,  -0.1758