Answer:
10 units and 157.84 units
Step-by-step explanation:
4
substitute t = 1 into the equation
h = - 16(1)² + 6 = - 16 + 6 = - 10
the value is negative since the ball travels down
the ball has travelled 10 units after 1 second
5
substitute t = 3.2 into the equation
h = - 16(3.2)² + 6 = - 16(10.24) + 6 = - 163.84 + 6 = - 157.84
the well is 157.84 units deep
Did you learn how to factor the difference of two squares ?
This thing is the difference of two squares.
The first term is the square of 5x .
The second term is the square of 4 .
When it's factored, it's
(sum of the square roots) x (difference of the square roots) .
25 x² - 16 = (5x + 4) times (5x - 4) .
To check it, go ahead and FOIL that out, and you'll get 25x²-16 .
Distribute the -4. Then combine like terms.
24 - 4(5y - 6z) + 3y - 7z =
= 24 - 20y + 24z + 3y - 7z
= - 20y + 3y + 24z - 7z + 24
= -17y + 17z + 24
