I am having troubles finding x, need an explanation

Answer: A

Step-by-step explanation: x=-2, y=3, z=-3

Answer:

A. -2, 3, -3

Step-by-step explanation:

x = 7 - 2y + z

y = 21 + 6x + 2z = 21 + 6×(7 - 2y + z) + 2z =

= 21 + 42 - 12y + 6z + 2z = 63 - 12y + 8z

13y = 63 + 8z

y = (63 + 8z)/13

2x + 2y - 3z = 11

2×(7 - 2y + z) + 2×(63 + 8z)/13 - 3z = 11

2×(7 - 2×(63 + 8z)/13 + z) + 2×(63 + 8z)/13 - 3z = 11

14 - 4×(63 + 8z)/13 + 2z + 2×(63 + 8z)/13 - 3z = 11

-2×(63 + 8z)/13 - z = -3

-2×(63 + 8z) - 13z = -39

-126 - 16z - 13z = -39

-29z = 87

z = -3

y = (63 + 8×-3)/13 = (63 - 24)/13 = 39/13 = 3

x = 7 - 2×3 + -3 = 7 - 6 - 3 = -2

One piece will be length x and the other piece will be 20 cm longer, so it will be x + 20 cm long.  

Added together the length of these two boards will equal 86 cm. So you can write an equation:  

x + (x + 20) = 86  

Remove the parentheses and add the two x's together to get:  

2x + 20 = 86

Subtract 20 from both sides:  

2x = 66  

Divide both sides by 2 and you have:  

x = 33  

The short piece is 33 cm and the other piece is 20 cm longer or 33 + 20 = 53 cm.

Answer:

The length of each side of the city is 250b

Step-by-step explanation:

Given

[tex]a = 20[/tex] --- tree distance from north gate

[tex]b =14[/tex] --- movement from south gate

[tex]c = 1775[/tex] --- movement in west direction from (b)

See attachment for illustration

Required

Find x

To do this, we have:

[tex]\triangle ADE \sim \triangle ACB[/tex] --- similar triangles

So, we have the following equivalent ratios

[tex]AE:DE = AB:CB[/tex]

Where:

[tex]AE = 20\\ DE = x/2 \\ AB = 20 + x + 14 \\ CB = 1775[/tex]

Substitute these in the above equation

[tex]20:x/2 = 20 + x + 14: 1775[/tex]

[tex]20:x/2 = x + 34: 1775[/tex]

Express as fraction

[tex]\frac{20}{x/2} = \frac{x + 34}{1775}[/tex]

[tex]\frac{40}{x} = \frac{x + 34}{1775}[/tex]

Cross multiply

[tex]x *(x + 34) = 1775 * 40[/tex]

Open bracket

[tex]x^2 + 34x = 71000[/tex]

Rewrite as:

[tex]x^2 + 34x - 71000 = 0[/tex]

Expand

[tex]x^2 + 284x -250x - 71000 = 0[/tex]

Factorize

[tex]x(x + 284) -250(x + 284)= 0[/tex]

Factor out x + 284

[tex](x - 250)(x + 284)= 0[/tex]

Split

[tex]x - 250 = 0 \ or\ x + 284= 0[/tex]

Solve for x

[tex]x = 250 \ or\ x =- 284[/tex]

x can't be negative;

So:

[tex]x = 250[/tex]

Answer:

26ft

Step-by-step explanation:

10^2 +24^2 =AB^2

AB=26

Answer: 26 ft

Step-by-step explanation:

a^2+b^2=c^2

10^2+24^2 = c^2

100+576=c^2

Sqrt 676 = c

C = 26

Answer:

3

Step-by-step explanation:

2x-xy

2(x)-(x)(y)

2(-1/2)-(-1/2)(8)

-1 - (-4)

-1 + 4

3

Answer:

3

Step-by-step explanation:

2x-xy

Let x = -1/2 and y = 8

2(-1/2) - (-1/2)(8)

Multiply

-1 - (-4)

Subtracting a negative is like adding

-1+4

Add

3

Answer:

The exact answer is 12*√2, if you need approximately answer it is 12*1.4= 16.8

Step-by-step explanation:

√50 + √98​ ​= √(25*2)+√(49*2)= √25√2+√49*√2= 5√2+7*√2=12*√2

Answer:

Plug -2 in for x of f(x)

--> -2^4 + 2(-2)^2 - 1

---> 23

f(-2) = 23

Step-by-step explanation:

A = 12.25cm2

P perimeter 14cm

Answer:

A=12.25cm²

P=14

It's the third option.

Completing the square yields

x ² + 9x + 7 = 0

(x ² + 9x + 81/4) + 7 = 81/4

(x + 9/2)² + 7 = 81/4

Now solving for x gives

(x + 9/2)² = 53/4

x + 9/2 = ± √(53/4) = ± √53/2

x = (-9 ± √53)/2

2 and 3 are the common factor of 24 and 60

Answer:

D

Step-by-step explanation:

inverse just means opposite so if its shown dividing it first then adding, then the inverse is multiplying then subtracting

Answer:

√65

Step-by-step explanation:

you have to use the pythagoras theorem to find x which is the hypotenuse

x²=7²+4²

x²=49+16

√x²=√65

x=√65

I hope this helps

Answer:

√9 × √6

√54

√27 × √2

Step-by-step explanation:

We can obtain the answer to the question given above as illustrated below:

3√6

Recall

a√b = √(a×a×b)

Thus,

3√6 = √(3×3×6)

3√6 = √(9 × 6)

Recall

√(a × b) = √a × √b

√(9 × 6) = √9 × √6

Therefore,

3√6 = √9 × √6

Recall

√9 × √6 = √(9 × 6)

√9 × √6 = √54

Thus,

3√6 = √54

Recall

√54 = √(27 × 2)

√54 = √27 × √2

Therefore,

3√6 = √27 × √2

Therefore,

3√6 = √9 × √6 = √54 = √27 × √2

The perimeter of a triangle is the summation of the three sides of the triangle. Base on the assumed values, the length of side BD is 2.

For [tex]\triangle ACD[/tex], the sides are: AC, AD and CD

So, the perimeter is:

[tex]P_{\triangle ACD} = AC + AD + CD[/tex]

For [tex]\triangle ABD[/tex], the sides are: AB, AD and BD

So, the perimeter is:

[tex]P_{\triangle ABD} = AB + AD + BD[/tex]

The difference in the perimeters is:

[tex]P_{\triangle ACD} - P_{\triangle ABD} =1 + \sqrt 3[/tex]

So, we have:

[tex](AC + AD + CD) - ( AB + AD + BD) =1 + \sqrt 3[/tex]

Open brackets

[tex]AC + AD + CD - AB - AD - BD =1 + \sqrt 3[/tex]

Evaluate like terms

[tex]AC + CD - AB - BD =1 + \sqrt 3[/tex]

Make BD the subject

[tex]BD = AC + CD - AB - (1 + \sqrt 3)[/tex]

The solution cannot be completed because the side lengths of [tex]\triangle ACD[/tex] and [tex]\triangle ABD[/tex] are not given; so, I will assume the following values.

[tex]AC =2; CD = 1; AB = \sqrt 3[/tex]

[tex]BD = AC + CD - AB - (1 + \sqrt 3)[/tex] becomes

[tex]BD = 2 + 1 + \sqrt 3 - (1 + \sqrt 3)[/tex]

Open bracket

[tex]BD = 2 + 1 + \sqrt 3 - 1 - \sqrt 3[/tex]

Evaluate like terms

[tex]BD = 2[/tex]

Base on the assumed values, the length of side BD is 2.

Read more about perimeters at:

https://brainly.com/question/6465134

Answer:

Step-by-step explanation:

First number is 1/10

Last letter is 1/26

The second digit is 1/9

The first letter is 1/25

1/10 * 1/26 * 1/9 * 1/25

0.00001709

This assumes no duplication is allowed,

If there are duplications

then 1/10 * 1/10 * 1/26 * 1/26

0.000014782

.

.

..

.

.............

Answer:

[tex]13+19=n+25[/tex]

[tex]n+25=13+19[/tex]

Add 13+19= 32

[tex]n+25=32[/tex]

Now Subtract 25 from both sides

[tex]n+25-25=32-25[/tex]

[tex]n=7[/tex]

OAmalOHopeO

Answer:

Step-by-step explanation:

Total amount = 200 mg + (13 days)×(180 mg)/day = 2620 mg

One 35 mL bottle contains (35 mL)×(10 mg)/mL) = 350 mg of medication.

(2620 mg)×(1 bottle)/(350 mg) ≈ 7.5 bottles

8 bottles are needed.

The demand equation illustrates the price of an item and how it relates to the demand of the item.

From the question, we have:

[tex]Plates = 300[/tex]

[tex]Price = 20[/tex]

The number of plates (x) decreases by 10, while the price (y) increases by 5. The table of value is:

[tex]\begin{array}{cccccc}x & {300} & {290} & {280} & {270} & {260} \ \\ y & {20} & {25} & {30} & {35} & {40} \ \end{array}[/tex]

The slope (m) is calculated using:

[tex]m = \frac{y_2 - y_1}{x_2 - x_1}[/tex]

So, we have:

[tex]m = \frac{25-20}{290-300}[/tex]

[tex]m = \frac{5}{-10}[/tex]

[tex]m = -\frac{1}{2}[/tex]

The equation of the demand is as follows:

The initial number of plates (300) decreases by 10 is represented as: (300 - 10x).

Similarly, the initial price (20) increases by 5 is represented as: (20 + 5x).

So, the demand equation is:

[tex]R(x) = (300 - 10x) \times (20 + 5x)[/tex]

Open the brackets to calculate the maximum revenue

[tex]R(x) =6000 + 1500x - 200x - 50x^2[/tex]

[tex]R(x) =6000 + 1300x - 50x^2[/tex]

Equate to 0

[tex]6000 + 1300x - 50x^2 =0[/tex]

Differentiate with respect to x

[tex]1300 - 100x =0[/tex]

Collect like terms

[tex]100x =1300[/tex]

Divide by 100

[tex]x =13[/tex]

So, the price at maximum revenue is:

[tex]Price= 20 + 5x[/tex]

[tex]Price= 20 + 5 * 13[/tex]

[tex]Price= 85[/tex]

In conclusion:

Read more about demand equations at:

https://brainly.com/question/21586143

Answer:

should be 192

Step-by-step explanation:

Answer:

20 km

Step-by-step explanation:

We can use ratios to solve

1 cm          4 cm

--------  = ------------

5 km          x km

Using cross products

1 * x = 4 * 5

x = 20

20 km

Answer:

1/5 = 4/x

Step-by-step explanation:

Each cm on the map represents 5 km. If it shows 4 cm apart of the map, you can use the proportion 1 cm : 5 km = 4 cm : x km.

Answer:

B. The question may not be directly stated.

Answer:

the the 3rd one Is the one

Answer: (7, 20)

Concept:

There are three general ways to solve systems of equations:

Since the question has specific requirements, we are going to use substitution to solve the equations.

Solve:

Given equations

y = 3x - 1

2x + 6 = y

Substitute the y value since both equations has isolated [y]

2x + 6 = 3x - 1

Add 1 on both sides

2x + 6 + 1 = 3x - 1 + 1

2x + 7 = 3x

Subtract 2x on both sides

2x + 7 - 2x = 3x - 2x

[tex]\boxed{x=7}[/tex]

Find the value of y

y = 3x - 1

y = 3(7) - 1

y = 21 - 1

[tex]\boxed{y=20}[/tex]

Hope this helps!! :)

Please let me know if you have any questions

The process of copying an angle through construction involve ensuring

that the distance between the two rays forming the angle is the same or

equal in the original and copy of the angle at a given equal distance from

the vertex of both angles

The step where the error occur is step 4. She measured the incorrect length

The reason for the above selection is as follows:

The steps to copy an angle are as follows;

A critical step in the copying process involves the finding the distance

between the initial line and the terminal line EF at a given distance DG =

AE from the angle vertex

The step where the error occur is in step 4. by opening the compass

between points A and E which are points on the same line and placing the

compass at point G on line l to draw an arc intersecting the arc created

from point D at H, thereby making the radial distance between the two lines

forming the angle, in the copied angle at a distance E from the vertex,

equal to AE rather than EF

Therefore, the error occurred in step 4. She measured the incorrect length

Learn more about the steps to copy an angle here:

https://brainly.com/question/4292471

Answer:

x > -2

Step-by-step explanation:

14 <-7x

or, 14/-7=-7x/-7

or, -2 < x

Answer:

24n^7/m^16

Step-by-step explanation:

Just simplify and rewrite what ever you get simplify again 2 times and now make the calculation as you see every big number is a whole number and is a pair.

Answer:

x = 2

Step-by-step explanation:

→ Simplify

x × ( 9 ) = 10 + 8

→ Further simplify

9x = 18

→ Divide both sides by 9

x = 2