1. 5 faces
2. 4 triangles
3. 6(4)1/2=12 in
4. 36in squared=91.44cm squared
5. 12(4)=48 in squared=121.92 cm sqaured
6. 82 in squared=208.28 cm squared

7 0

3 years ago

I need to find out how long it takes him to hit the water

bearhunter [10]

Answer:

1.26

Step-by-step explanation:

When he hits the water, the height will be 0. Substitute h=0.

$0 = -16t^2+2t+23$

Solve using the quadratic equation.

$x = \frac{-b+/-\sqrt{b^2-4ac} }{2a}$

Substitute a = -16, b=2, and c=23.

$x = \frac{-b+/-\sqrt{b^2-4ac} }{2a}\\\\x = \frac{-2+/-\sqrt{(-2)^2-4(-16)(23)} }{2(-16)}\\\\x = \frac{-2+/-\sqrt{4+1472} }{-32}\\\\x = \frac{-2+/-\sqrt{1476} }{-32}\\x = \frac{-2+/-38.4}{-32}\\x = \frac{-2+38.4}{-32}=\frac{36.6}{-32}=-1.14\\or\\x = \frac{-2-38.4}{-32}=\frac{-40.4}{-32}=1.26$