Solved 7t^2 + 19t - 6 = 0 by inspection & formula but get different result using 'completing square'.
Rearrange :t^2 + 19t/7 = 6/7
Complete the square :
t^2 + 19t/7 + (19/14)^2 = 6/7 + (19/14)^2
(t + 19/14)^2 = 6/7 + (19/14)^2
t = (+/-)sqrt(6/7 + (19/14)^2) - 19/14
Doing the numbers :
t = 1.64 - 1.8 = -0.16
or
t = -1.64 - 1.8 = -3.44
No more space for the rest!

Question

Solved 7t^2 + 19t   - 6 = 0 by inspection & formula but get different result using 'completing square'.
Rearrange :t^2  + 19t/7     = 6/7
Complete the square : 
t^2  + 19t/7 + (19/14)^2 = 6/7 + (19/14)^2
(t + 19/14)^2                    = 6/7 + (19/14)^2
t  = (+/-)sqrt(6/7 + (19/14)^2) - 19/14
Doing the numbers :
t = 1.64 - 1.8   = -0.16
       or
t = -1.64 - 1.8  = -3.44
No more space for the rest!

anonymous · Answer

u r doing bad the calculatuon in the calculator for this equation t  = (+/-)sqrt(6/7 + (19/14)^2) - 19/14
i got x= 0.28

jdoe0001 · Answer

are you supposed to "complete the square" to get the values of "t"?