Solve the following equation by completeing the square 3x2
Solve the following equation by completeing the square
3x2 + x -1/6 = 0
Find the real solutions of the following equation using the quadratic formula.
x2 - 6x -5= 0
Solution
1) 3x^2 + x -1/6
Divide by 3 :
x^2 + x/3 -1/2 =0
x^2 +x/3 + (1/6)^2 - ( 1/6)^2 -1/2 =0
( x +1/6)^2 - 1/36 -1/2 =0
(x+1/6)^2 = ( 1+18)/36
So, taking square root on both sides:
(x+1/6 = + / - sqrt(19)/6
x = -1/6 + / - sqrt(19)/6 ( Roots of solution)
2) x^2 -6x -5 =0
Using quadratic equation formula:
x = ( -b + /- sqrt( b^2 -4ac)/2a
= ( 6 + /- sqrt( 36 - (-4)*1*(-5) )/2
= ( 6 + /- sqrt(56)/2
x = 3 + / - sqrt14) ( Solution)
