Solve this quadratic equation using the quadratic formula. 2x 2 - 2x = 1

( 2 + √3 ) / 2, ( 2 - √3 ) / 2

Step-by-step explanation:

2x^2 - 2x = 1

2x^2 - 2x - 1 = 0

Here,

a = 2

b = - 2

c = - 1

D = b^2 - 4ac

D = ( - 2 )^2 - 4 ( 2 ) ( - 1 )

= 4 + 8

D = 12

x = - b ± √D / 2a

= - ( - 2 ) ± √12 / 2 ( 2 )

= 4 ± 2√3 / 4

= 2 ( 2 ± √3 ) / 4

= 2 ± √3 / 2

x = ( 2 + √3 ) / 2, ( 2 - √3 ) / 2

it is a. 4.2 because 7.6-3.4 gets the remaining length of 4.2. i might be wrong but i am pretty sure this is the answer.