How do you complete the square to solve x^2+x=19/4?
2 Answers
Jun 12, 2017
x=-1/2+sqrt5
x=-1/2-sqrt5
Explanation:
Given -
x^2+x=19/4
x^2+x+1/4=19/4+1/4=(19+1)/4=20/4
(x+1/2)^2= 20/4
(x+1/2)=+-sqrt (20/4)=+-(sqrt5xxcancelsqrt(4))/cancelsqrt(4)
x+1/2=+-sqrt 5
x=-1/2+sqrt5
x=-1/2-sqrt5
Jun 12, 2017
Explanation:
Remember the identity
or
Hence to complete square we must add
or
or
and using the identity
Hence either
or