Step-by-step explanation:
Given that,
A motor boat travels 60 miles down a river in 3 hours but takes 5 hours to return upstream,
We know that,
Speed = distance/time
The rate while moving downstream[tex]=\dfrac{60}{3}=20\ mph[/tex]
The rate while moving upstream [tex]=\dfrac{60}{5}=12\ mph[/tex]
The rate of the boat in still water is the average of these:
[tex]v_s=\dfrac{20+12}{2}=16\ mph[/tex]
The rate of the current is the difference between the boat speed and actual speed = 16 mph - 12 mph = 4 mph
Hence, this is the required solution.
Charlene is a video game designer and wants to make sure that her games can be played on all types of screens. In order for the games to work on both devices with a standard aspect ratio and those with widescreen aspect ratios, the playable area of the games should have an aspect ratio of 3:2. This means that the width is equal to times the height. On one type of tablet, the playable area of the game on the screen is 54 square inches. Write and solve a system of equations to determine the dimensions of the playable area. A. The playable area has a width of 13.5 inches and a height of 9 inches. B. The playable area has a width of 6 inches and a height of 9 inches. C. The playable area has a width of 6 inches and a height of 4 inches. D. The playable area has a width of 9 inches and a height of 6 inches.
Answer:
The playable area has a width of 9 inches and a height of 6 inches.
Step-by-step explanation:
There are a number of ways you can get there.
1. Check the answers to see which have the right area and aspect ratio.
A: area = 24 in² — does not match 54 in²
B: area = 54 in², aspect ratio 6:9 = 2:3 — does not match 3:2 aspect ratio
C: area = 54 in², aspect ratio 9:6 = 3:2 — matches problem statement
D: area = 121.5 in² — does not match 54 in²
2. If the screen were 3:2 (inches), its area would be 6 in². The area of 54 in² is 9 times that value, so the actual screen dimensions are √9 = 3 times 3:2. That is, they are width:height = 9:6 inches — matches selection C.
3. You can write equations for width and height and solve.
w/h = 3/2
wh = 54
Substituting w=3/2·h into the second equation gives
... (3/2)h·h = 54
... h² = 36 . . . . . multiply by 2/3
... h = √36 = 6 . . . . square root, result in inches
Answer:
D. The playable area has a width of 9 inches and a height of 6 inches.
Step-by-step explanation:
if the playable area is 54 and that such ratio of dimensions is 3:2
Then we are basically being asked to find the factor of ratios below that also multiply to get 54
54 = 9 x 6 and this is also a ratio of 3:2
As 3(3 + 2) = 54
and as width was asked first when ratio was given 3:2
The width therefore is 9 and the height is 6
So answer is D
4x = -12? dgdgdgdgdgdg
Answer:
-3
Step-by-step explanation:
X=-12/4
X=-3
hope it helps
Answer:
-3
Step-by-step explanation:
4x= -12
4x/4 = -12/4
x = -3
Please help please reply
Answer:
hypotenuse:15
Step-by-step explanation:
Pythagorean Theorem is a^2 + b^2 = c^2
"a" and "b" are the legs, "c" is the hypotenuse
9^2 + 12^2 = 225
[tex]\sqrt{225\\[/tex]
hypotenuse = 15
The height of a square pyramid where the lateral area equals 240 cm sq. and the edges of the base are 12cm
Answer:
The height is 8cm
Step-by-step explanation:
Given
[tex]L_A = 240cm^2[/tex] --- lateral area
[tex]a = 12cm[/tex] --- base lengths
Required
The height of the pyramid
The lateral area of a square pyramid is:
[tex]L_A = a\sqrt{a^2 + 4h^2[/tex]
So, we have:
[tex]240 = 12\sqrt{12^2 + 4h^2[/tex]
[tex]240 = 12\sqrt{144 + 4h^2[/tex]
Divide both sides by 12
[tex]20 = \sqrt{144 + 4h^2[/tex]
Square both sides
[tex]400 = 144 + 4h^2[/tex]
Collect like terms
[tex]4h^2 = 400 - 144[/tex]
[tex]4h^2 = 256[/tex]
Divide by 4
[tex]h^2 = 64[/tex]
Take square roots
[tex]h = 8[/tex]
Can somebody help me out please
Answer:
Brainly's honor code doesn't allow quiz questions to be posted.
"Students are never allowed 2 post questions directly from tests, quizzes, and assessments, or copy answers found on Brainly during tests, quizzes, and assessments."
Jenny made 200 bracelets. She sold 64% of the bracelets at a craft fair.
a. How many bracelets did she sell?
b. How many bracelets were not sold?
Step-by-step explanation:
shslsfauahcaiscwrwpagw6wpwfwyw
Answer:
Jenny sold 128 braclets. 72 bracelets weren't sold.
Step-by-step explanation:
IMPORTANT FORMULA: TO CONVERT A NUMBER TO A PERCENT, YOU HAVE TO MULTIPLY BY 100. TO CONVERT A PERCENT TO A NUMBER, YOU HAVE TO DIVIDE BY 100.
a) How many bracelets did she sell?
Using the formula that is shown above, I can conclude that 64%=64/100=32/50=16/25
Jenny sold 64% of the 200 bracelets.
In mathematics, the word "of" means multiplication.
64% of 200 = 16/25 * 200 = 128
Jenny sold 128 braclets.
to answer part 2, 200 bracelets - 128 bracelets = 72 bracelets.
72 bracelets weren't sold.
Help me plz I need to get a good score
Answer:
x+59 =180( sum of linear pair )
x=180-59
x=121
A local grocery store charges for oranges
based on weight as shown in the graph below.
Find the price (dollars per kilogram) of
oranges at the grocery store.
dollars per kilogram
Answer:
3 dollars
Step-by-step explanation:
Khan academy said so
Come up with an example of three side lengths that can not possibly make a triangle, and explain how you know.
Answer:
3, 5 and 15
Step-by-step explanation:
According to the triangle inequality theorem, the lengths of any two sides of a triangle must add up to more than the length of the third side. This means that you cannot draw a triangle with side lengths 3, 5 and 15, since 3 + 5 is less than 15.
add negative 4 plus negative 6
-10
thats it, thats what i know
2.) Find the zeros of the quadratic function y = x2 – 3x + 2 by factoring method.
Answer:
The zeros are 1 and 2
Step-by-step explanation:
Given
[tex]y =x^2 - 3x + 2[/tex]
Required
The zeros
[tex]y =x^2 - 3x + 2[/tex]
Expand
[tex]y =x^2 - 2x-x + 2[/tex]
Factorize
[tex]y =x(x - 2)-1(x - 2)[/tex]
Factor out x - 2
[tex]y =(x - 1)(x - 2)[/tex]
Set to 0
[tex](x - 1)(x - 2)=0[/tex]
Solve for x
[tex]x - 1 = 0 \to x =1[/tex]
[tex]x - 2 = 0 \to x =2[/tex]
Hence, the zeros are 1 and 2
Help plz ??
This is really urgent. If anyone knows the answer plz plz help me
Answer:
A
because range is all values of Y but in negative side it is infinity but in positive side range is 4
the line below are parallel. If green line has a slope of 2/5 what is the slope of the red line? enter your answer as an integer or fraction in lowest terms
Answer:
if they are parallel it would almost be opposite but they would be negative instead of positive
The table shows a linear relationship between x and y.
х
у
-20
96
-12
60
-6
33
-2
15
What is the rate of change of y with respect to x?
Answer:
[tex] -\frac{9}{2} [/tex]
Step-by-step explanation:
Rate of change of x and y can be calculated using the following formula and using any two given pair of values from the table:
Rate of change = [tex] \frac{y_2 - y_1}{x_2 - x_1} [/tex]
Using (-12, 60) and (-6, 33).
Where,
[tex] (-12, 60) = (x_1, y_1) [/tex]
[tex] (-6, 33) = (x_2, y_2) [/tex]
Plug is the values
Rate of change = [tex] \frac{33 - 60}{-6 -(-12)} [/tex]
Rate of change = [tex] \frac{-27}{6} [/tex]
Simplify
Rate of change = [tex] \frac{-9}{2} [/tex]
Rate of change = [tex] -\frac{9}{2} [/tex]
Triangles A B C and A double-prime B double-prime C double-prime are shown. Triangle A double-prime B double-prime C double-prime is smaller and to the right of triangle A B C. Which transformations could have taken place to map △ABC to △A"B"C"? a reflection and a dilation a rotation and a dilation a translation and a dilation a reflection and a translation
C. a translation and a dilation
Step-by-step explanation:
the other person isn't wrong they just put it in the wrong order
Answer:c
Step-by-step explanation:took the test
Write the equation of the circle with center C(-5,8) and radius = 7
Answer:
( h + 5 )^2 + ( y - 8 ) ^2 = 49
Step-by-step explanation:
Equation of a circle:
( x - h )^2 + ( y - k )^2 = r^2
Where ( h , k ) = center and r = radius
We are given that the circle has a center at ( -5 , 8 ) meaning that h = -5 and k = 8
We are also given that the circle has a radius of 7 meaning that r = 7
Now that we have identified each variable we plug the values into the equation
( h - (-5)^2 + ( y - 8 )^2 = 7^2
Our final step is to simplify
we get that the equation of the circle is
( h + 5 )^2 + ( y - 8 ) ^2 = 49
By the way ^ means exponent
Can someone help me please
Answer:
n = -1
Step-by-step explanation:
n^2 + 5n + 1 = 3n
N^2 +2n +1 = 0 (subtract 3n from both sides)
(n+1)(n+1) = 0 (factor
n+1 =0; n= -1
n+1 = 0 ; n=-1
find all possible values for each expression
9514 1404 393
Answer:
D
Step-by-step explanation:
The sine function is negative only for angles greater than 180°. This eliminates choice B.
The sine function is periodic with a period of 360°, eliminating choices A and C.
The only viable choice is D, which is the correct one.
F=(2xy +z³)i + x³j + 3xz²k find a scalar potential and work done in moving an object in the field from (1,-2,1) to (3,1,4)
Step-by-step explanation:
Given:
[tex]\textbf{F} = (2xy + z^3)\hat{\textbf{i}} + x^3\hat{\textbf{j}} + 3xz^2\hat{\textbf{k}}[/tex]
This field will have a scalar potential [tex]\varphi[/tex] if it satisfies the condition [tex]\nabla \times \textbf{F}=0[/tex]. While the first x- and y- components of [tex]\nabla \times \textbf{F}[/tex] are satisfied, the z-component doesn't.
[tex](\nabla \times \textbf{F})_z = \left(\dfrac{\partial F_y}{\partial x} - \dfrac{\partial F_x}{\partial y} \right)[/tex]
[tex]\:\:\:\:\:\:\:\:\: = 3x^2 - 2x \ne 0[/tex]
Therefore the field is nonconservative so it has no scalar potential. We can still calculate the work done by defining the position vector [tex]\vec{\textbf{r}}[/tex] as
[tex]\vec{\textbf{r}} = x \hat{\textbf{i}} + y \hat{\textbf{j}} + z \hat{\textbf{k}}[/tex]
and its differential is
[tex]\textbf{d} \vec{\textbf{r}} = dx \hat{\textbf{i}} + dy \hat{\textbf{j}} + dz \hat{\textbf{k}}[/tex]
The work done then is given by
[tex]\displaystyle \oint_c \vec{\textbf{F}} • \textbf{d} \vec{\textbf{r}} = \int ((2xy + z^3)\hat{\textbf{i}} + x^3\hat{\textbf{j}} + 3xz^2\hat{\textbf{k}}) • (dx \hat{\textbf{i}} + dy \hat{\textbf{j}} + dz \hat{\textbf{k}})[/tex]
[tex]\displaystyle = (x^2y + xz^3) + x^3y + xz^3|_{(1, -2, 1)}^{(3, 1, 4)}[/tex]
[tex]= 422[/tex]
Chad has a rope that is 15 yards long. How many pieces of rope measuring 5/7 of a yard can he divide his rope into?
A. 28
B. 21
C. 35
D. 14
Answer:
Chad can divide his rope in 21 pieces. (Answer B)
Step-by-step explanation:
To solve we divide.
15 divided by 5/7 is what we need to know.
When dividing fractions it is the same thing as multiplying by the reciprocal (flipped version of the fraction).
[tex]15[/tex] ÷ [tex]\frac{5}{7}[/tex] = 15 × [tex]\frac{7}{5}[/tex]
[tex]\frac{15}{1}[/tex] × [tex]\frac{7}{5}[/tex] = [tex]\frac{105}{5}[/tex]
[tex]\frac{105}{5}[/tex] = 21
Chad can divide his rope in 21 pieces.
Answer:
21 pieces
Step-by-step explanation:
Divide (5/7 yd / piece) into 15 yds:
15 yds
----------------------- = 21 pieces
(5/7 yd / piece)
PLSSSS ASAPPP!!!!!!!!!!
Find the length of the missing side in the right triangle shown below.
A)169
B)7,056
C)None of these answers are correct
D)7,225
E)13
Answer:
D. my answer for your question
how to write 403.225 in words and how do i get the answer. Thanks!!!!
Using the graph of f(x) and g(x), where g(x) = f(k⋅x), determine the value of k.
1. 4
2. 1/4
3. -1/4
4. −4
Please help!!
Answer:
1. 4
Step-by-step explanation:
the slope of:
f(x) = 10/2=5
g(x) = 10/½=20
so, g(x) = f(4.x)
=> k = 4
MAKE SURE YOU ARE RIGHT ANSWER PLEASE I WILL PUT THE BRAINIEST ANSWER
FIND THE VOLUME OF THE SPHERE
Step-by-step explanation:
Formula:- 4/3*Pi*r^3
= 4/3*22/7*(1/2)^3
Please mark me as brainliest
Help please !!! I will mark brainlist!!
Answer:
x= -0.182 and +4
hope it helps
have a nice day
What is the distance between T(9, −5) and the center of the circle with equation (x – 6)2 + (y + 1)2 =10?
Step-by-step explanation:
first, determine the coordinates values like x =9 and y=-5
so x-6 =3
Which of the following phrases are expressions?
Answer:
C ,D , E just follow it . thank me later if its right
Answer:
E
Step-by-step explanation:
(10+7)(50+1)
=17×51
=867
- 10 + x < - 2 what is the solution of the inequality shown below
Answer:
x<8
Step-by-step explanation:
QUESTION 1
Determine the work done by the force
F=31+] + k in moving an object through
displacement T = 7 -7 -K
It's difficult to make out what the force and displacement vectors are supposed to be, so I'll generalize.
Let θ be the angle between the force vector F and the displacement vector r. The work W done by F in the direction of r is
W = F • r cos(θ)
The cosine of the angle between the vectors can be obtained from the dot product identity,
a • b = ||a|| ||b|| cos(θ) ==> cos(θ) = (a • b) / (||a|| ||b||)
so that
W = (F • r)² / (||F|| ||r||)
For instance, if F = 3i + j + k and r = 7i - 7j - k (which is my closest guess to the given vectors' components), then the work done by F along r is
W = ((3i + j + k) • (7i - 7j - k))² / (√(3² + 1² + 1²) √(7² + (-7)² + (-1)²))
==> W ≈ 5.12 J
(assuming F and r are measured in Newtons (N) and meters (m), respectively).
Select the correct answer.
What is the solution to this equation?
log3 (4x) – 2log3x =2
A. 36
B. 9/4
C. 4/9
D. 1/36
9514 1404 393
Answer:
C. 4/9
Step-by-step explanation:
There are a couple of ways you can do this.
[tex]\log_3{4x}-2\log_3{x}=2\\\\\log_3{4}+\log_3{x}-2\log_3{x}=2\\\\\log_3{4}-2=\log_3{x}\\\\4\cdot3^{-2}=x\qquad\text{take antilogs}\\\\\boxed{x=\dfrac{4}{9}}\\\\\textsf{or}\\\\\dfrac{4x}{x^2}=3^2\qquad\text{take antilogs}\\\\\dfrac{4}{9}=x\qquad\text{cancel $x$, multiply by $\dfrac{x}{9}$}[/tex]