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2 years ago

X S2.0.2

Mathematics

1 answer:

dexar [7]2 years ago

8 0

9514 1404 393

Answer:

320 m after 8 seconds
5.6 seconds, 10.4 seconds to height of 290 m

Step-by-step explanation:

To find the height at 8 seconds, evaluate the formula for t=8.

S(t) = -5t^2 +80t

S(8) = -5(8^2) +80(8) = -320 +640 = 320

The height of the rocket is 320 meters 8 seconds after takeoff.

To find the time to 290 meters height, solve ...

S(t) = 290

290 = -5t^2 +80t

-58 = t^2 -16t . . . . . . . divide by -5

6 = t^2 -16t +64 . . . . . complete the square by adding 64

±√6 = t -8 . . . . . . . . . take the square root

t = 8 ±√6 ≈ {5.551, 10.449}

The rocket is at 290 meters height after 5.6 seconds and again after 10.4 seconds.

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The director of an animal shelter need to raise more than $50,000 during a fundraiser. Write an inequality that represents the a

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Jonah's house and his grandparents house are 8,046.72 meters apart what is this difference in miles. A.4 miles B.5 miles C.7 mil

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In a company there are 33 male and 42 female staff. Calculate the percentage of male and female staffs

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Answer: 44%, 56%

Step-by-step explanation:

Given

A company has 33 males and 42 female staff

So, the total staff is the sum of male and female

$\Rightarrow \text{Total=}33+42\\\Rightarrow \text{Total=}75$

The percentage of male staff is

$\Rightarrow \text{Male }\%=\dfrac{33}{75}\times 100\\\\\Rightarrow \text{Male }\%=44\%$

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7 0

2 years ago

A piece of cardboard has the dimensions (x + 15) inches by (x) inches with the area of 60 in 2 . Write the quadratic equation th

pochemuha

Answer:

$x^2 + 15x - 60 = 0$

The actual dimension is 18.28 by 3.28

Step-by-step explanation:

Given

Dimension:

$(x + 15)\ by\ x$

$Area = 60in^2$

Required

Determine the quadratic equation and get the possible values of x

Solving (a): Quadratic Equation.

The cardboard is rectangular in shape.

Hence, Area is calculated as thus:

$Area = Length * Width$

$60= (x + 15) * x$

Open Bracket

$60= x^2 + 15x$

Subtract 60 from both sides

$x^2 + 15x - 60 = 0$

<em>Hence, the above represents the quadratic equation</em>

Solving (b): The actual dimension

First, we need to solve for x

This can be solved using quadratic formula:

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

Where

$a = 1$

$b = 15$

$c = -60$

So:

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

$x = \frac{-15 \± \sqrt{15^2 - 4*1*-60}}{2*1}$

$x = \frac{-15 \± \sqrt{225 + 240}}{2}$

$x = \frac{-15 \± \sqrt{465}}{2}$

$x = \frac{-15 \± \21.56}{2}$

Split:

$x = \frac{-15 + 21.56}{2}$ or $x = \frac{-15 - 21.56}{2}$

$x = \frac{6.56}{2}$ or $x = \frac{-36.36}{2}$

$x = 3.28$ or $x = -18.18$

But length can't be negative;

So:

$x = 3.28$

The actual dimensions: $(x + 15)\ by\ x$ is

$Length =3.28 +15$

$Length =18.28$

$Width = x$

$Width =3.28$

<em>The actual dimension is 18.28 by 3.28</em>

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3 years ago

13+[8×16-(24+5×b)÷2]÷3-45=0

alexgriva [62]

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b = 88/-b
b= -17.6

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