Question

solve the following equation by completing square 7x square-2x-1=0​

Answer 1

Answer:

Step-by-step explanation:

Two solutions were found :

x =(2-√32)/14=(1-2√ 2 )/7= -0.261

x =(2+√32)/14=(1+2√ 2 )/7= 0.547

Answer 2

solution:-

=> 7x²-2x-1=0

Solving 7x²-2x-1 = 0 by Completing The Square .

x²-(2/7)x-(1/7) = 0

x²-(2/7)x = 1/7

add both side 1/49

=> x²-(2/7)x+(1/49) = 8/49 ...............(1)

=> x²-(2/7)x+(1/49) = (x-(1/7))²..........(2)

from ( 1 ) and ( 2 )

(x-(1/7))² = 8/49

x = 1/7 + √ 8/49

has two solutions:

x = 1/7 + √ 8/49

or

x = 1/7 - √ 8/49

Note that √ 8/49 can be written as

√ 8 / √ 49 which is √ 8 / 7

I hope it helps you........