URGENT - How would I write 2 less than triple a number?

a boy is standing on a pole of height 14.7m throws a stone upwards. it moves in a vertical line slightly away from the pole and

fomenos

Answer:

The time taken for the upward motion is 1 second. The same time is taken for the downward motion

It reaches a maximum height of 4.9 meters.

Step-by-step explanation:

The equation of motion is:

$x(t) = -4.9t^{2} + 9.8t$

Since the term which multiplies t squared is negative, the graph is concave down, that is, x increases until the vertex, where it reaches it's maximum height, then it decreases.

Vertex of a quadratic equation:

Quadratic equation in the format $x(t) = at^{2} + bt + c$

The vertex is the point $(t_{v}, x(t_{v}))$ , in which

$t_{v} = -\frac{b}{2a}$

In this question:

$x(t) = -4.9t^{2} + 9.8t$

So $a = -4.9, b = 9.8$

Vertex:

$t_{v} = -\frac{9.8}{2*(-4.9)} = 1$

The time taken for the upward motion is 1 second.

$x(t_{v}) = x(1) = 9.8*1 - 4.9*(1)^{2} = 4.9$

It reaches a maximum height of 4.9 meters.

Downward motion:

From the vertex to the ground.

The ground is t when x = 0. So

$-4.9t^{2} + 9.8t = 0$

$4.9t^{2} - 9.8t = 0$

$4.9t(t - 2) = 0$

$4.9t = 0$

$t = 0$

Or

$t - 2 = 0$

$t = 2$

It reaches the ground when t = 2 seconds.

The downward motion started at the vertex, when t = 1.

So the duration of the downward motion is 2 - 1 = 1 second.

5 0

2 years ago

A piece of bad news about your hotel goes viral. If each person, spreads the news to 5 people within 1 minute, how long will it

Lady_Fox [76]

A 20,000,000

Hope my answer helped

5 0

2 years ago

Read 2 more answers

Deremine the slope and y-intercept y=x+5

const2013 [10]

Slope:1
Y intercept:5

8 0

2 years ago

Isabella save 2 nickels today, if she doubles the number of Nicole, she saves every day, how many days, including today, will it

Elden [556K]

Answer:

8 days

Step-by-step explanation:

On day 8, Isabella will save 256 nickels, bringing her total to 510.

_____

The number of nickels saved on day n is 2^n. The total is 2^(n+1)-2.

_____

The above can be written down from your knowledge of binary sequences. If you want a more formal development, read on.

__

The number of nickels saved on day n is a geometric sequence with first term 2 and common ratio 2. The n-th term of the sequence is ...

an = a1·r^(n-1) = 2·2^(n-1) = 2^n

The sum of n terms of the sequence is ...

S = a1(r^n -1)/(r -1) = 2(2^n -1)/(2-1)

S = 2^(n+1) -2

__

We want S > 500, so ...

500 < 2^(n+1) -2

502 < 2^(n+1)

251 < 2^n

log(251) < n·log(2)

n > log(251)/log(2)

n > 7.97 . . . . . . . . 8 days or more to save more than 500 nickels

3 0

2 years ago

a jewler buys a ring from an artisan for 85$. He sells the ring at his store at 135% increase in price. What is the retail price

ELEN [110]

A jeweler buys a ring from an artisan for 85$. He sells the ring at his store at 135% increase in price. What is the retail price? PLEASE SHOW UR WORK!!!

1.35(135%) x 85( the price it was bought for)

= $114.75

4 0

2 years ago