The combined mass of two children is 75lbs. The first child is four times the mass of the second child. What are the masses of the two children?

Answer:

d=2

Step-by-step explanation:

We are given equation:

sqrt(4y-3)=d-y

Squaring both sides gives:

4y-3=(d-y)^2

Applying the identity (x+y)^2=x^2+2xy+y^2 on right:

4y-3=d^2-2dy+y^2

Now let's y=7:

4(7)-3=d^2-2d(7)+(7)^2

Simplify:

25=d^2-14d+49

Subtract 25 on both sides:

0=d^2-14d+24

Factor left:

0=(d-12)(d-2) since -2+-12=-14 and -2(-12)=24

This gives d=12 or d=2.

The d that makes d-y or I mean d-7 negative will give us y=7 as extraneous

Since 2-7 is -5, then d=2 is what we are looking for.

Check:

sqrt(4y-3)=d-y

Set d=2: sqrt(4y-3)=2-y

Now solve for y:

Square both sides: 4y-3=4-4y+y^2

Subtract 4y and 3 on both sides: 0=7-8y+y^2

Reorder right side: 0=y^2-8y+7

Factor: 0=(y-7)(y-1) since -7+-1=-8 and -7(-1)=7

This gives y=7 or y=1.

Plugging in y=7 for a check to this equation gives:

sqrt(4×7-3)=2-7

Sqrt(25)=-5

5=-5 which is not true which is what we wanted

Let assume hours be x.

1 hour = 60 minutes

x hour = 330 minutes

[tex] \bf \large \rightarrow \: \: \frac{1}{60} \: \times \: \frac{x}{330} \: \: \: \small\rm({\red{ Cross \: \: Multiplying }}) \\ [/tex]

[tex]\bf \large \rightarrow \: \: 60x \: = \: 330[/tex]

[tex]\bf \large \rightarrow \: \: x \: = \: \cancel \frac{330}{60} \: = \: 5.5 \\ [/tex]

Total hours in a day is 5.5

The average American student is in class 5.5 hours a day.

A measurement unit is a standard quality used to express a physical quantity. Also it refers to the comparison between the unknown quantity with the known quantity.

We have to given that;

The average American student is in class 330 minutes a day.

We know that;

⇒ 1 hours = 60 minutes

⇒ 1 minute = 1/60 hours

Hence, We can change the unit as;

⇒ 330 minutes = 330 / 60 hours

                        = 5.5 hours

Thus, It is equal to 5.5 hours.

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Answer:

option d. is the correct answer

Answer:

x^2 +2x+xy +2y

Step-by-step explanation:

(x + y) (x + 2)

FOIL

first x*x = x^2

outer  x*2 =2x

inner y*x= xy

last = y*2 =2y

Add together

x^2 +2x+xy +2y

Answer:

Step-by-step explanation:

F - First ; O - Outside ;  I - inside  ; L -last

(x + y)(x + 2) = x*x + x*2 +y*x +y*2

                    = x² + 2x + xy +2y

Answer:

Step-by-step explanation:

Volume = pi * r^2 * h

r = 2 feet

h = 10 feet

Volume = 3.14 * 2^2 * 10

Volume = 125.6 cubic feet

1 cubic foot contains 7.48 gallons

125.6 cubic feet contain 7.48 * 125.6 = 930.488

The tank contains 930.49 gallons.

Answer:

Step-by-step explanation:

First step plug the numbers into the equation.

-10/(5+2) = (-10/5) + (-10/2)

Solve both sides of the equation separately.

-10/(5+2) Use distributive property, multiply both 5 and 2 by -10.

= -50 + (-20) = -70

-10/5 + -10/2 Multiply the fractions so they can be added together.

-10/5*2 = -20/10  -10/2*5 = -50/10

-20/10 + -50/10 = -70

Now you have solved both equations and they are both equal to -70, so you have verified that the equations are equal to each other because they both equal -70.

Answer:

(-5,2)

Step-by-step explanation:

Answer:

(5 , 2)

Step-by-step explanation:

F(-5 , 2)

After reflection F'(5 , 2)

The rule for reflection over y-axis is

Original point(x , y)   :  After reflection:  (-x,y)

x-coordinate will change its sign and y-coordinate remains same

Answer:

9y + 24

Step-by-step explanation:

2(3y + 6) - 3(-4 - y)

= 6y + 12 - 3(-4 - y)

= 6y + 12 + 12 + 3y

= 9y + 12 + 12

= 9y + 24

Answer:

Step-by-step explanation:

Surface Area of Cylinder = 2πrh+2πr^2

2π(3)(12) + 2π(3)^2

= 282.7 yd^3

answered by g a u t h m a t h

Answer:

It's D I sure about it correspond means identical... The matching number

Answer:

C

Step-by-step explanation:

The center of the base is the center of the circle

The center of the circle is C

Answer:

The answer to your question would be x=12. Equation is worked out below

Step-by-step explanation:

5 /2 x−7= 3 /4 x+14

5 /2 x-3/4x − 7 =  3 /4 x-3/4x +14

7/ 4 x−7=14

7 /4 x−7+7=14+7

7/ 4 x=21

do the opposite of 7/4x (division)

7/4 / 7/4x = 21 / 7/4

4/7 / 7/4x (cross each other out) = 21 / 4/7

x=12

Answer:

[tex] \frac{5}{2}x - 7 = \frac{3}{4} x + 14 \\ \frac{5}{2} x - \frac{3}{4} x = 14 + 7 \\ \frac{7}{4} x = 21 \\ x = \frac{21 \times 4}{7} \\ x = 12[/tex]

I hope I helped you^_^

Answer:

348 km³

Does the answer help you?

Answer:

the original population of the city is 7,505,833

Step-by-step explanation:

Given;

new of the population of the city, Y = 9,007,000

the percentage increase of the city, = 20% = 0.2

Let the original population of the city = X

New population, Y = X  + 0.2X

                           Y = X(1 + 0.2)

                           Y = X(1.2)

                           Y = 1.2X

                           X = Y/1.2

                           X = (9,007,000) / 1.2

                           X = 7,505,833

Therefore the original population of the city is 7,505,833

Step-by-step explanation:

please mark this answer as brainlist

Answer:

b = 19.2

Step-by-step explanation:

9.6 = ½b

=> 9.6 × (2/1) = b

=> 9.6 × 2 = b

=> 19.2 = b

Answer:

11,968

Step-by-step explanation:

I'm not sure, but I think its 11,968

Answer:

Step-by-step explanation:

We know, for square

[tex](side)^2=(Area)\\=>X^2=8\\[/tex]

∴[tex]X=2\sqrt{2}[/tex] unit

[tex]Now, Side=3X[/tex]

[tex]Then,Area=(3X)^2=(3*2\sqrt{2} )^2=(6\sqrt{2} )^2=72 sq. unit[/tex]

hope you have understood this...

pls mark my answer as the brainliest

The area of square of side 3X is 72 square unit.

The square is a 4 sided figure, each side of the square is equal and make a right angle.

The area of square having sided a unit can be given by a² square unit.

Given that,

Area of square having side X is 8.

Since, formula for area of square having side X is X².

Implies that,

X² = 8

X = 2√2

The area of square having side 3X
side =3 × 2√2

side = 6√2

The area of square = (6√2)²

                                = 36 x 2

                                = 72

The area of square is 72 square unit.

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Answer:

quadratic trinomial

Step-by-step explanation:

(8x^2 + 3x) – (12x^2 - 1)

Distribute the minus sign

8x^2+3x-12x^2+1

Combine like terms

-4x^2+3x+1

This is a quadratic since the highest power of x is 2

This is a trinomial since there are 3 terms

Answer:

1st option

Step-by-step explanation:

3×2+5y=15

5y=15-6

y=9/5

Answered by GAUTHMATH

Answer:

6^2 = 36

Step-by-step explanation:

10^2 = 10 * 10 = 100

4^3 = 4 * 4 * 4 = 64

10^2 - 4^3= 100 - 64 = 36 = 6^2

Hi there!  

»»————-　★　————-««

I believe your answer is:  

[tex]6^2[/tex]

»»————-　★　————-««  

Here’s why:  

⸻⸻⸻⸻

[tex]\boxed{\text{Calculating the answer...}}\\\\10^2 - 4^3\\---------------\\\rightarrow 10^2 = 100\\\\\rightarrow 4^3 = 64\\\\\rightarrow 100 - 64 = \boxed{36}\\\\\text{Since we know that '36' is a perfect square, we can rewrite our answer as: } \boxed{6^2}[/tex]

⸻⸻⸻⸻

»»————-　★　————-««  

Hope this helps you. I apologize if it’s incorrect.  

Answer:

- 14

Step-by-step explanation:

x = - 6

x^2 - 9x + 4

= ( - 6 )^2 - 9 ( - 6 ) + 4

= 36 + 54 - 4

= 36 - 50

= - 14

Answer:

[tex]94[/tex]

Step-by-step explanation:

[tex]x^2 - 9x + 4[/tex]

[tex](−6 {)}^{2} −9 (−6) + 4[/tex]

[tex]36 − 9 (−6) + 4[/tex]

[tex]36 + 54 + 4[/tex]

[tex]90+4[/tex]

[tex]94[/tex]

Answer:

D 2/3

Step-by-step explanation:

Rise over run. The x values is -3 and 9 which is the distance or run between the dots. Find the distance by finding which number is between then so -3+x=9 where x is 12. The y values are -7 and 1. Find y where -7+y=1 where y is 8. That is the rise. So the rise is 8 and that is over the run, 12, gives you 8/12 which can be simplified to 2/3.

Question isn't well formatted, a picture if the question is attached below.

Answer:

1 / 4

Step-by-step explanation:

From the plot, each dot represent a gamer ; therefore, the total number of gamers will be counting all the dots ;

Total number of gamers = 24

Fraction of gamers that have 7 / 8 of the way to go ;

This means that they have 7/8 of the way left to proceed to next level ;

The fraction is : 1 - 7/8 = 1 /8

This means the number of of people whose progress are on 1/8 ; this is 6

Hence, fraction of gamers that have 7/8 of the way to go :

6 / 24 = 1 / 4

Answer:

ARC= 15.7

ARC= 2(3.14)10(90/36)

Step-by-step explanation:

Answer:

Step-by-step explanation:

The rate of change for the interval between x = 2 and x = 6 is simply asking you for the slope of the line that connects these 2 coordinates. If you were in calculus, you could find the instantaneous slope at any point on this parabola, but you're not quite that lucky yet, so we will go about it the only way we can:

by finding the slope. Remember, that slope is the same thing as rate of change.

[tex]m=\frac{y_2-y_1}{x_2-x_1}[/tex] and filling in:

[tex]m=\frac{14-2}{6-2}=\frac{12}{4}=3[/tex]

Answer:

b = 3

Step-by-step explanation:

Substitute the y- coordinate 15 into the equation , that is

15 = 5x ( divide both sides by 5 )

3 = x

This is the x- coordinate of the point , so b = 3

Answer:

90°

Step-by-step explanation:

Angle C = arccos((84²+13²-85²)/(2×84×13))

= arccos(0/2184)

= arccos(0)

= 90°

Answered by GAUTHMATH