Answer:
A bird drops a stick to the ground from a height of 80 feet. The equation 0=−16x2+64x+80 gives the number of seconds that have passed when it hits the ground. After about how many seconds did the stick hit the ground?
Step-by-step explanation:
h = -16t^2 + 80 Stick hits the ground when h = 0:
0 = -16t^2 + 80
16t^2 = 80
t^2 = 80/16 = 5
t = POSITIVE root 5 (due to the real world nature of the problem)
t approximately 2.236 seconds.
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Graph is a downward opening parabola with h-intercept of 80, t-intercept(s) of sqrt(5), - sqrt(5)
Symmetric about h-axis, though I would only graph on the right side of the h-axis since
that is where t >= 0.
<h3>Given</h3>
- room height is x feet
- room length is 3x feet
- room width is 3x feet
- a door 3 ft wide by 7 ft tall
<h3>Find</h3>
- The net area of the wall, excluding the door
<h3>Solution</h3>
The area of the wall, including the door, is the room perimeter multiplied by the height of the room. The room perimeter is the sum of the lengths of the four walls.
... gross wall area = (3x +3x +3x +3x)·x = 12x²
The area of the door is the product of its height and width.
... door area = (7 t)×(3 ft) = 21 ft²
Then the net wall area, exclusive of the door is ...
... net wall area = gross wall area - door area
... net wall area = 12x² -21 . . . . square feet
Answer:
Step-by-step explanation:
22
Step-by-step explanation:
- Number of red = 2
- Number of blue = 5
- Number of green = 3
- total number of marbles = 10
<h3>
probability of not choosing a red marble = 1--choosing a red marble.</h3>
<u>Because</u><u> </u><u>probability</u><u> </u><u>is</u><u> </u><u>always</u><u> </u><u>one</u><u>(</u><u>1</u><u>)</u><u>.</u>
<em>Probability</em><em> </em><em>=</em>
<em>
</em>
<em>
</em>
<em>
</em>
<em>Is</em><em> </em><em>the</em><em> </em><em>probability</em><em> </em><em>of</em><em> </em><em>not</em><em> </em><em>choosing</em><em> </em><em>a</em><em> </em><em>red</em><em> </em><em>marble</em><em>.</em>
Answer:
35.
Step-by-step explanation:
3+5 = 8, 7 goes into 35 5 times. Therefore its 35