Can someone help me please.

Three women, Chantel, Marissa, and Qian, enjoy running laps around a circular track. Each women runs at a constant speed. It tak

lubasha [3.4K]

It takes 150 seconds for Qian to complete the track.

Let she runs the track in the clockwise direction.

In 60 seconds, she runs $\frac{60}{150}$ = $\frac{2}{5}$ th of the track.

Since she meets Marissa, who is running in the opposite (counter clockwise) direction in every 60 seconds, Marissa should have completed $\frac{3}{5}$ th of the track.

Chantel meets Marissa in every 300 seconds.

So, in 60 seconds, she advances Marissa by $\frac{1}{5}$ th of the track.

Hence, in 300 seconds, Qian, Marissa and Chantel all meets at the starting point.

ALITER;

Marissa meets Qian in every 60 seconds.

So, Marissa and Qian meet each other in 60th, 120th, 180th, 240th and 300th second.

But, it is given that Chantel meets Marissa in every 300 seconds.

So, in 300 seconds, Qian, Marissa and Chantel meet each other.

6 0

3 years ago

Find the value of x such that the area of a triangle whose vertices have coordinates (6, 5), (8, 2) and (x, 11) is 15 square uni

Serjik [45]

Answer:

$x =12\ or\ -8$

Step-by-step explanation:

Given

$(x_1,y_1) = (6,5)$

$(x_2,y_2) = (8,2)$

$(x_3,y_3) = (x,11)$

$Area = 15$

Required

Find x

The area is calculated as thus:

$Area = \frac{1}{2}|x_1(y_2 - y_3) + x_2(y_3 - y_1) + x_3(y_1 - y_2)|$

Substitute values

$15 = \frac{1}{2}|6*(2 - 11) + 8*(11 - 5) + x(5 - 2)|$

$15 = \frac{1}{2}|6*(-9) + 8*(6) + x(3)|$

$15 = \frac{1}{2}|-54 + 48 + 3x|$

$15 = \frac{1}{2}|-6 + 3x|$

Multiply through by 2

$2 * 15 = \frac{1}{2}|-6 + 3x| * 2$

$30 = |-6 + 3x|$

Remove absolute sign

$30 = -6 + 3x\ or\ -30 = -6 + 3x$

Add 6 to both sides

$36 = 3x\ or\ -24 = 3x$

Divide by 3

$12 = x\ or\ -8 = x$

$x =12\ or\ -8$

<em>So, the coordinates are (-8, 11) or (12,11)</em>

3 0

2 years ago

Which statement best describes the pattern of association between the variables x and y shown in the scatter plot

Kryger [21]

Answer:

if i were to answer...i would go for B, but dont use my answer if u disapprove cuz I, myself, isnt sure

Step-by-step explanation:

8 0

3 years ago

Given f(x) =

sergejj [24]

Answer:

A

Step-by-step explanation:

We are given the function:

$\displaystyle f(x) = \left\{ \begin{array}{ll} 2\cos(\pi x) \text{ for } x \leq -1 \\ \\ \displaystyle \frac{2}{\cos(\pi x)}\text{ for } x > -1 \end{array} \right.$

And we want to find:

$\displaystyle \lim_{x\to -1}f(x)$

So, we need to determine whether or not the limit exists. In other words, we will find the two one-sided limits.

Left-Hand Limit:

$\displaystyle \lim_{x\to-1^-}f(x)$

Since we are approaching from the left, we will use the first equation:

$\displaystyle =\lim_{x\to -1^-}2\cos(\pi x)$

By direct substitution:

$=2\cos(\pi (-1))=2\cos(-\pi)=2(-1)=-2$

Right-Hand Limit:

$\displaystyle \lim_{x\to -1^+}f(x)$

Since we are approaching from the right, we will use the second equation:

$=\displaystyle \lim_{x\to -1^+}\frac{2}{\cos(\pi x)}$

Direct substitution:

$\displaystyle =\frac{2}{\cos(\pi (-1))}=\frac{2}{\cos(-\pi)}=\frac{2}{(-1)}=-2$

So, we can see that:

$\displaystyle \displaystyle \lim_{x\to-1^-}f(x)=\displaystyle \lim_{x\to -1^+}f(x) =-2$

Since both the left- and right-hand limits exist and equal the same thing, we can conclude that:

$\displaystyle \lim_{x \to -1}f(x)=-2$

Our answer is A.

8 0

3 years ago

EASY QUESTION. HELP NEED PLZ.

Setler79 [48]

Answer:

1: 30 degrees

Step-by-step explanation:

In Physics, we have the law of reflection. This law states that when light rays hit the smooth surface of mirror or any smooth polished surface, the angle of incidence is equivalent to the angle of reflection.

Mathematically:

Angle of incidence = Angle of reflection

From the above question, the angle of incidence is on a smooth plane mirror = 30°

Since:

Angle of incidence = Angle of reflection

30° = 30°

Therefore, based on the law of reflection, the Angle of reflection = 30°

3 0

3 years ago