Plz answer it’s timed

Answer:

x=8, y=0, z=-3

Step-by-step explanation:

Preferable is substitution because there is less room for mistakes but its long so here goes bare with me on this one :D

Name your equations

4x+2y-5z=47 (first eq)

x-2y+6z=-10 (second eq)

9x-7y-z=75 (third eq)

Lets take the easiest eq to isolate one variable lets take 2nd eq

[tex]x-2y+6z=-10\\x=2y-6z-10[/tex]

now this becomes our fourth eq

now again take the easiest eq to isolate another variable lets take the 3rd eq

[tex]9x-7y-z=75\\9x-7y-75=z[/tex]

now this becomes our fifth eq

and now plug in our fifth eq in the fourth eq because we now have z in terms of x and y

[tex]x=2y-6z-10\\x=2y-6(9x-7y-75)-10\\x=2y-54x+42y+450-10\\x+54x=2y+42y+450-10\\55x=44y+440\\\\x=\frac{44y+440}{55}[/tex]

and now we got our sixth equation which is x only in terms of y.

now we plug in our sixth equation in our fifth eq to get z in terms of y only

[tex]z=9x-7y-75\\\\z=9(\frac{44y+440}{55}) -7y-75\\z=\frac{396y+3960}{55} -7y-75\\z=\frac{396y+3960-385y-4125}{55} \\z=\frac{11y-165}{55}[/tex]

now we have our seventh eq and x &z in terms of just one variable y , now we put equation of z and x which is our sixth eq and seventh eq in our first eq.

[tex]4x+2y-5z=47\\\\4(\frac{44y+440}{55})+2y-5(\frac{11y-165}{55}) =47\\\\\frac{176y+1760}{55} +2y-47=\frac{11y-165}{11} \\\\\frac{176y+1760}{55} -\frac{11y-165}{11} -47=-2y\\\\\frac{176y+1760}{55}-(y-15) -47=-2y\\\\\frac{176y+1760}{55} -y-32=-2y\\\\\\frac{176y+1760}{55}=-2y+y+32 \\\\176y+1760=55(-y+32)\\176y+1760=-55y+1760\\176y-55y=1760-1760\\121y=0\\y=0[/tex]

and now finally we got y=0 now we need the value of x and z, put the value of y=0 in our seventh eq (z equation)

[tex]z=\frac{11y-165}{55} \\\\z=\frac{11(0)-165}{55} \\\\z=\frac{-165}{55}\\\\z=-3[/tex]

and now we put the value of y=0 in our sixth eq (x equation)

[tex]x=\frac{44y+440}{55} \\\\x=\frac{44(0)+440}{55} \\\\x=\frac{440}{55} \\\\x=8[/tex]

and now we got all the three values and hence the solution of the system of equation is

x=8, y=0, z=-3

Answer:

Step-by-step explanation:

Let the surface of the water be at 0m

If a polar bear was sitting on the top of an ice float that was 2.5 meters above the surface of the water, the distance between the ice float and the surface of the water will be:

= 2.5 - 0

= 2.5m

If the polar bear dove 6.5 meters from the top of the float into the water to catch a seal, to get the distance between the bear under the water to the sea level, we will use the expression:

2.5 + x = 6.5

Subtract 2.5 from both sides

2.5+x -2.5 = 6.5-2.5

x = 4.0m

Hence the equation that best represents how far below the surface the polar bear dove is 2.5 + x = 6.5 where x is the distance between the polar bear below and the surface of the water

Answer:

Sure! Can you tell me the digits of pi?

Step-by-step explanation:

Answer:

6 more teachers are required.

Step-by-step explanation:

Total number of students = 616

No of teachers = 616/28= 22

Increase in students = 18%

                                = 18/100*616= 110.88= 111

Total number of students = 616+111= 727

Decrease in teachers = 9%

                                 = 9/100*22= 1.98= 2

New number of teachers= 20

Now Average is 28 students per teacher so

727/28= 25.96= 26 teachers are required for the total number of 727 students. The school has already 20 teachers so they need 6 more teachers.

Answer:

1. 35 2. 145 3. 35 4. 90 5. 145

Step-by-step explanation:

Answer:

7

Step-by-step explanation:

Multiply - and -13 first which is 13 subtract 6 from 13 and you will get 7 which is the answer

Hope this helps!

Answer:

positive

Step-by-step explanation:

Answer:

It means it is usually positive

Step-by-step explanation:

The positive sign is invisible if it is at the beginning of an equation number, if it is moved to the other side of the equal sign, than it turns the opposite charge. Hope this answers your question :)

Answer:

3x2 - x + 10 when x=-4 plug in -4 for x 3(-4)^2 -(-4)+10

3(16)+4+10

3x16= 48

48+4+10= 62

Suzie's work is incorrect because of her negative distributions

Step-by-step explanation:

Answer:

3/8 = 0.375

Step-by-step explanation:

I used a calculator

Answer:

the correct answer is 2

Step-by-step explanation:

Answer: x=2

Step-by-step explanation:

Answer:

the answer is D

Step-by-step explanation:

The equation y = -16x² + 64x represents the given parabola that represents the height in feet of an object above the ground T seconds after it was launched from the ground.

A function is a relation between a dependent and independent variable. We can write the examples of functions as -

y = f(x) = ax + b

y = f(x, y, z) = ax + by + cz

Given is a graph that shows the height in feet of an object above the ground {T} seconds after it was launched from the ground.

The given graph is a parabola. A quadratic equation represents a parabola.

The quadratic equation will have two roots at the point on which it cuts the {x} axis.

Consider the equation in option {C} as -

y = -16x² + 64x

For the point (4, 0), we can check the graph as -

0 = - 16 x 4 x 4 + 64 x 4

0 = 0

For the point (0, 0), we can check -

0 = 0 + 64 x 0

0 = 0

Therefore, the equation y = -16x² + 64x represents the given parabola that represents the height in feet of an object above the ground T seconds after it was launched from the ground.

To solve more questions on functions, visit the link below-

https://brainly.com/question/30194223

#SPJ3

Answer:

504 * 0.12 = 60.48

Step-by-step explanation:

math

Answer:

its 60.48

Step-by-step explanation:

Convert 12% to a decimal which is 0.12

then do the sum 0.12x504

Answer:

Mia is incorrect. 32% of the students say climbing trees is their favorite.

Step-by-step explanation:

Percentage of the students that chose climbing trees = number of students that chose climbing trees ÷ total number of students surveyed × 100

Number of students that chose climbing trees = 8

Total number of students = those that chose riding bike + those that chose climbing trees + those that say swimming = 12 + 8 + 5 = 25

Therefore,

% of the students that say climbing trees = [tex] {8}{25}*100 = \frac{800}{25} = 32 [/tex].

Mia is wrong.

32% say climbing trees is their favorite. NOT 40%.

Answer:

b or a

Step-by-step explanation:

If bus A arrives after 14 minutes and bus B arrives after 20 minutes, then both buses will arrive at 140 minutes.

Given:

Find the least common multiple of 14 minutes and 20 minutes

14 minutes = 14, 28, 42, 56, 70, 84, 98, 112, 126, 140, 154, 168, 182, 196, 210, 224, 238, 252, 266, 280....

20 minutes = 20, 40, 60, 80, 100, 120, 140, 160, 180, 200, 220.....

Therefore, the least common multiple of 14 minutes and 20 minutes is 140 minutes.

Learn more about LCM:

https://brainly.com/question/10749076

Answer:

12 (p/2 + 17.50) = 750 equation can be used to get regular price of enrollment.

Step-by-step explanation:

So when a new student gets enrolled by paying a $17.50 application fee and gets a value of price halved at p/2

where p = regular price of enrollment

So in reality, for the student to be enrolled he/she must pay = (p/2) + $17.50 application fee to be able to get that special offer.

So Twelve new students enrolled, meaning they paid: 12 (p/2 + 17.50 application fee)

The amount they all paid is $750.

To get the regular price of enrollment from the price that included the application fees, the equation to use would be: 12 (p/2 + 17.50) = 750

The correct answer is 12 ([tex]\frac{p}{2}[/tex] + 17.50) =750

Explanation:

In mathematics, an equation represents equality; this means mathematical expressions are placed to the sides of the equality sign and these have the same value. Moreover, if an equation is written based on a situation or description, the values should include the appropriate mathematical symbols (+, -, x, etc) depending on how each of the factors in the equation relates.

In the case presented, it is known the total collected was $750 and due to this, this value should be placed to one side of the symbol =. Moreover, this value was obtained as students paid 17.50 of the application fee plus half of the price. This can be written as [tex]\frac{p}{2}[/tex] (a half price or price divided 2) + 17.50 (application fee). Finally, these two values should be multiplied by 12 (number of students that paid). According to this, the equation is 12 ([tex]\frac{p}{2}[/tex] + 17.50) =750.

Answer:

the 3 one xD

Step-by-step explanation:

i know i am bulted       D I F F E R E N T   ~(T-T)~

Answer:

It’s it shows that Reece could work around his disadvantages

Step-by-step explanation:

Given:

Susan divides the fraction [tex]\dfrac{5}{8}[/tex] by [tex]\dfrac{1}{16}[/tex].

Her friend Robyn divides [tex]\dfrac{5}{8}[/tex] by [tex]\dfrac{1}{32}[/tex].

To find:

The quotient of Susan and Robyn.

Solution:

Susan divides the fraction [tex]\dfrac{5}{8}[/tex] by [tex]\dfrac{1}{16}[/tex].

[tex]\dfrac{\dfrac{5}{8}}{\dfrac{1}{16}}=\dfrac{5}{8}\times \dfrac{16}{1}[/tex]

[tex]\dfrac{\dfrac{5}{8}}{\dfrac{1}{16}}=\dfrac{80}{8}[/tex]

[tex]\dfrac{\dfrac{5}{8}}{\dfrac{1}{16}}=10[/tex]

So, Susan's quotient is 10.

Her friend Robyn divides [tex]\dfrac{5}{8}[/tex] by [tex]\dfrac{1}{32}[/tex].

[tex]\dfrac{\dfrac{5}{8}}{\dfrac{1}{32}}=\dfrac{5}{8}\times \dfrac{32}{1}[/tex]

[tex]\dfrac{\dfrac{5}{8}}{\dfrac{1}{32}}=5\times 4[/tex]

[tex]\dfrac{\dfrac{5}{8}}{\dfrac{1}{32}}=20[/tex]

So, Robyn's quotient is 20.

Since 20>10, therefore, Robyn will get greater quotient.

Answer:

0=17

Step-by-step explanation:

2X - 10=7 +2x

-10 = 7

7 is fasle

i believe the answer is 17

Answer:

80 m

Step-by-step explanation:

From the question;

Initial velocity, u, = 20m/s

Time = 15 s

deceleration= -2.5 m/s² ------negative acceleration

The formula to apply is;

v²=u²+2as

where v is the final velocity = 0m/s and s is the total distance travelled.

Applying the formula as;

v²=u²+2as

0²=20²+ 2*-2.5*s

0=400+ -5s

0=400-5s

5s= 400

s= 400/5 = 80

s= 80 m

The total distance travelled is  80 m.

7, because 8/4 = 2 which means that 1 guest = $2. So if we do 14 / 2 to see how many guests that would be, it's 7.

Answer:

7

Step-by-step explanation:

Well if it's $8 for 4 people then you have to divide to get the rate:

$8/4 = [tex]\frac{2}{person}[/tex]

now you can divide the disired amount to get the number of people:

$14/ [tex]\frac{2}{person}[/tex] = 7 people

Answer:

2.68

Step-by-step explanation:

answer:

5.33333333333