All categories

3 years ago

Please I don't understand help me

Mathematics

1 answer:

Murrr4er [49]3 years ago

6 0

Answer:

6.2 seconds

Step-by-step explanation:

To translate into math, the question is asking you "for what approximate t value does h = 0?" In order to solve, you can plug in 0 for h and solve for t.

0 = -16t^2 + 620

-620 = -16t^2

620 = 16t^2

38.75 = t^2

$\sqrt{38.75}$ = t

6.2 ~~ t (rounding to the nearest tenth)

Don't forget your units!

Let me know if you need anything explained in more detail; I'm happy to help.

You might be interested in

Multiply and rewrite the system: 16푥−10푦=10 −8푥−6푦=6 solving for elimination

Artyom0805 [142]

Hmmm I think 16 - 10 = 10 ( - 8 - 6 ) = 6

5 0

3 years ago

Use the substitution method to solve each linear system. 4x - 3y = -13,-2x + y = 4

Contact [7]

Answer:

The solutions to the system of equations are:

$x=\frac{1}{2},\:y=5$

Step-by-step explanation:

Given the system of the equations

$\begin{bmatrix}4x-3y=-13\\ -2x+y=4\end{bmatrix}$

Isolate x for for 4x-3y=-13

$4x-3y=-13$

$4x=-13+3y$

Divide both sides by 4

$x=\frac{-13+3y}{4}$

substitute y=5

$x=\frac{-13+3\cdot \:5}{4}$

$x=\frac{1}{2}$

The solutions to the system of equations are:

$x=\frac{1}{2},\:y=5$

8 0

3 years ago

17<br> Write<br> percentage.<br> 20

enot [183]

Answer:

$\large \boxed{85\%}$

Step-by-step explanation:

17/20

Multiply by the conjugate 5/5.

(17 × 5)/(20 × 5)

85/100

Apply rule : a/100 = a%

85/100 = 85%

5 0

3 years ago

A medical devices company wants to know the number of hours its MRI machines are used per day. A previous study found a standard

4vir4ik [10]

The company has to study 199 machines.

In statistics, the standard deviation is a measure of the amount of variation or dispersion of a set of values. A low standard deviation indicates that the values tend to be close to the mean of the set, while a high standard deviation indicates that the values are spread out over a wider range.

It is given that;

Margin of error E = 0.7

Confidence interval 98% = 1-0.98 = 0.02

Standard deviation = 6 hours

Number of MRI machines needed per day n, = [(z alpha/2 * SD)/E]²

Z alpha/2 = 1.645 at alpha = 0.1

Inputting these values into n we have that

[(1.645*6)/0.7]²

= 14.1²

= 198.81 is approximately equal to 199

The company has to study 199 machines.

To know more about standard deviation visit: brainly.com/question/475676

8 0

2 years ago

If f(x) = 2x2 - 5 and g(x) = x2 - 4x - 8, find (f - g)(x).

oksano4ka [1.4K]

Answer:

B. ) x² + 4x + 3

Step-by-step explanation:

(f-g)(x) = f(x) - g(x) =

(2x²-5) - (x²-4x-8) =

2x² - x² + 4x + 8 - 5 =

x² + 4x + 3

8 0

4 years ago