Solve x2+6x=7 by completing the square. which is the solution set of the equation?

x = - 7, x = 1

Step-by-step explanation:

Given

x² + 6x = 7

To complete the square

add ( half the coefficient of the x- term )² to both sides

x² + 2(3)x + 9 = 7 + 9

(x + 3)² = 16 ( take the square root of both sides )

x + 3 = ± = ± 4 ( subtract 3 from both sides )

x = - 3 ± 4

x = - 3 - 4 = - 7

x = - 3 + 4 = 1

Solution set = { - 7, 1 }

54 km / hours

step-by-step explanation:

we need to convert seconds to hours

60 seconds = 1 minutes

60 minutes = 1hour

15 m         60 second   60 minutes

  * *         = 54000 meters/ hour

second     1 minute             1 hour

now we need to convert meters to km

1000 m = 1 km

54000 m       1 km

*   = 54 km / hours

hour               1000m