A ball is thrown in the air from a ledge. Its height in tesspresented by
R -16(x^2
- 5x-6), where x is the number of seconds since the ball has
been thrown. The height of the ball is 0 feet when it hits the ground.
How many seconds does it take the ball to reach the ground?

6 .74 seconds

Step-by-step explanation:

The height of the ball is given by the equation:

When the ball hit the ground, then;

We discard x=-0.74 since time is not negative.

Therefore the ball hit the ground after 6.74 seconds.

answer is x<

option 3 . (5x + 1) - (-10x + 6)

step-by-step explanation:

option 1 :

(4x + 3) + (-9x + 4)

or 4x+3 -9x + 4

or -5x + 7

option 2

(x - 2) - (6x - 9)

or x-2-6x + 9

or -5x + 7

option 3

(5x+ + 6)

or 5x + 1 + 10x -6

or 15x -5

option 4

-4x+2x+7-3x

-7x + 2x + 7

-5x + 7

hence only option 3 did   not satisfy the given simplify expression.