Factorization using formula

Quadratic equation is given by

a\[x^2\]+bx+c=0

we can find the value of 'x' using factorization using formula when factoring numbers is not possible.the formula is given by

x=\[\frac{-(b)+/-\sqrt{b^2-4\times a\times c}}{2\times a}\]

case 1: when \[b^2-4\times a\times c\] is positive 

case 2: when \[b^2-4\times a\times c\] is negative (example will be given in further calculations)

example for case 1:

\[x^2-9x+20\]=0

x=\[\frac{-b+/-\sqrt{b^2-4\times a\times c}}{2\times a}\]

given a=1,b=-9,c=20

substituting in formula 

x=\[\frac{-(-9)+/-\sqrt{-9^2-4\times 1\times 20}}{2\times 1}\]

x=\[\frac{9+/-\sqrt{81-80}}{2}\]

x=\[\frac{9+/-\sqrt{ 1}}{2}\ \]

x= \[\frac{9+/- 1}{2}\ \]

we shall find two values of x 

when sign is +

x =\[\frac{9+1}{2}\ \] =5

when sign is -

x=\[\frac{9-1}{2}\ \] =4

\[\therefore \] x= 5,4

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