Choose a system of equations with the same solution as the following system

Answer:

she bought 7 cards

Step-by-step explanation

7x5=35 and im sure there is tax

Answer:

[tex]\Large \boxed{b=2}[/tex]

Step-by-step explanation:

-5+2(10b-2)=31

Expand brackets.

-5+20b-4=31

-9+20b=31

Add 9 on both sides.

20b=40

Divide both sides by 20

b=2

Answer:

Step-by-step explanation:

-5+2(10b-2)=31

Multiply the terms in the bracket

That's

- 5 + 20b - 4 = 31

Group like terms

Send the constants to the right side of the equation

That's

20b = 31 + 4 + 5

Simplify

20b = 40

Divide both sides by 20

We have the final answer as

Hope this helps you

Answer:  see proof below

Step-by-step explanation:

You will need the following identities to prove this:

[tex]\tan\ (\alpha-\beta)=\dfrac{\tan \alpha-\tan \beta}{1+\tan \alpha\cdot \tan \beta}[/tex]

[tex]\cos\ 2\alpha=\cos^2 \alpha-\sin^2\alpha[/tex]

LHS → RHS

[tex]\dfrac{2\tan\ (45^o-A)}{1+\tan^2\ (45^o-A)}\\\\\\=\dfrac{2\bigg(\dfrac{\tan\ 45^o-\tan\ A}{1+\tan\ 45^o\cdot \tan\ A}\bigg)}{1+\bigg(\dfrac{\tan\ 45^o-\tan\ A}{1+\tan\ 45^o\cdot \tan\ A}\bigg)^2}\\\\\\=\dfrac{2\bigg(\dfrac{1-\tan\ A}{1+\tan\ A}\bigg)}{1+\bigg(\dfrac{1-\tan\ A}{1+\tan\ A}\bigg)^2}\\\\\\=\dfrac{2\bigg(\dfrac{1-\tan A}{1+\tan A}\bigg)}{1+\bigg(\dfrac{1-2\tan\A+\tan^2 A}{1+2\tan A+\tan^2A}\bigg)}\\[/tex]

[tex]=\dfrac{2\bigg(\dfrac{1-\tan A}{1+\tan A}\bigg)}{\dfrac{(1+2\tan A+\tan^2A)+(1-2\tan A+\tan^2 A)}{1+2\tan A+\tan^2A}}\\\\\\=\dfrac{2\bigg(\dfrac{1-\tan A}{1+\tan A}\bigg)}{\dfrac{2+2\tan^2A}{1+2\tan A+\tan^2A}}\\\\\\=\dfrac{2\bigg(\dfrac{1-\tan A}{1+\tan A}\bigg)}{2\bigg(\dfrac{1+\tan^2A}{(1+\tan A)^2}\bigg)}\\\\\\=\dfrac{\bigg(\dfrac{1-\tan A}{1+\tan A}\bigg)}{\bigg(\dfrac{1+\tan^2A}{(1+\tan A)^2}\bigg)}[/tex]

[tex]=\dfrac{1-\tan A}{1+\tan A}}\times \dfrac{(1+\tan A)^2}{1+\tan^2A}\\\\\\=\dfrac{1-\tan^2 A}{1+\tan^2 A}\\\\\\=\dfrac{1-\dfrac{\sin^2 A}{\cos^2 A}}{1+\dfrac{\sin^2 A}{\cos^2 A}}\\\\\\=\dfrac{\bigg(\dfrac{\cos^2 A-\sin^2 A}{\cos^2 A}\bigg)}{\bigg(\dfrac{\cos^2 A+\sin^2 A}{\cos^2 A}\bigg)}\\\\\\=\dfrac{\cos^2 A-\sin^2 A}{\cos^2 A+\sin^2 A}\\\\\\=\dfrac{\cos^2 A-\sin^2 A}{1}\\\\\\=\cos^2 A-\sin^2 A\\\\\\=\cos 2A[/tex]

cos 2A = cos 2A   [tex]\checkmark[/tex]

Triangle inequality theorem:

In any triangle, the length of any side must be:

For the problem you have:

x must be greater than 8.0 - 2.5 and less than 8.0 + 2.5

5.5 < x < 10.5

Answer:

5.5<x<10.5

Step-by-step explanation:

Answer:

convert them to decimasls

Step-by-step explanation:

convert thhem to decimals to make it easier

Answer:

1/2 2/4 4/8 6/12 9/18

Step-by-step explanation:

Answer:C and F are correct

Step-by-step explanation:

got it right on edge

Answer:

3^1 or 3

3^5 * 3^-4 are 3^5-4

so, 3^1!

Hope it helps!

Answer:

3^1

Step-by-step explanation:

Since the bases are the same and we are multiplying we can add the exponents

a^b * a^c = a^(b+c)

3^5 * 3^-4

3^ (5+-4)

3^1

Answer:

[tex]d=\sqrt{73}[/tex]

Step-by-step explanation:

[tex]Q(5, -1)[/tex]

[tex]P(-3, 2)[/tex]

Using the distance formula:

[tex]d=\sqrt{(x_{2}-x_{1})^2+(y_2+y_1)^2}[/tex]

[tex]d=\sqrt{(-3-5)^2+(2-(-1))^2}[/tex]

[tex]d=\sqrt{(-8)^2+(3)^2}[/tex]

[tex]d=\sqrt{64+9}[/tex]

[tex]d=\sqrt{64+9}[/tex]

[tex]d=\sqrt{73}[/tex]

[tex]d\approx 8.5[/tex]

Answer:

1. EF = 65m

2. DF = 73m

Step-by-step explanation:

1. EF = height of the building = h = 33 / tan 27 = 65m

2. DF = sqrt (65² + 33²) = 73m

The building is 64.76 meters long and 73 meters far from the top of the building to the tip of the shadow.

From the triangle DEF, we find the value of EF by using tan function.

tan function is a ratio of opposite side and adjacent side.

tan(27)= 33/FE

0.5095 = 33/FE

Apply cross multiplication:

FE=33/0.5095

FE=64.76

Now DF is the hypotenuse, we find it by using pythagoras theorem.

DF²=DE²+EF²

DF²=33²+64.76²

DF²=1089+4193.85

DF²=5282.85

Take square root on both sides:

DF=72.68

In a triangle the the sum of three angles is 180 degrees.

∠D + 27 +90 =180

∠D + 117 =180

Subtract 117 from both sides:

∠D =63 degrees.

Hence, the building is 64.76 meters long and 73 meters far from the top of the building to the tip of the shadow.

To learn more on trigonometry click:

https://brainly.com/question/25122835

#SPJ4

Answer:

1 1/2 miles / hour

Step-by-step explanation:

We want distance / time

3/4 miles

---------------

1/2 hour

3/4 ÷ 1/2

Copy dot flip

3/4 * 2/1

3/2

1 1/2 miles / hour

Answer:

D

Step-by-step explanation:

Multiple (3/4)  by 2 to find the information for one hour)

6/4 in one hour

3/2 or 1 + 1/2 mi/h

D is the answer

Answer:

x = 75

Step-by-step explanation:

FGE is a straight line so it equals 180 degrees

FGA + AGC + CGE = FGE

x + 90 + 15 = 180

Combine like terms

x+ 105 = 180

Subtract 105 from each side

x = 180-105

x = 75

Answer:

x = 75º

Step-by-step explanation:

The Vertical Angle Theorem shows that:

∠CGE ≅ ∠DGF

So:

∠DGF = 15º

∠AGD = 90º

90º - 15º = 75º

x = 75º

Answer:

36

Step-by-step explanation:

There would be three on each edge. (Five, minus the two ends that have 3 sides painted.)

A cube has 12 edges.

12x3=36

Answer:

d = √8

d ≈ 2.82843

Step-by-step explanation:

Distance Formula: [tex]d = \sqrt{(x_2-x_1)^2+(y_2-y_1)^2}[/tex]

Simply plug in our coordinates into the distance formula:

[tex]d = \sqrt{(-3 + 5)^2+(-8 + 6)^2}[/tex]

[tex]d = \sqrt{(2)^2+(-2)^2}[/tex]

[tex]d = \sqrt{4+4}[/tex]

[tex]d = \sqrt{8}[/tex]

To find the decimal, simply evaluate the square root:

√8 = 2.82843

Answer:

Step-by-step explanation:

Let the points be A and B

A ( - 5 , - 6 ) ⇒ ( x₁ , y₁ )

B ( -3 , - 8 )⇒( x₂ , y₂ )

Now, let's find the distance between these two points:

AB = [tex] \mathsf{ \sqrt{ {(x2 - x1)}^{2} + {(y2 - y1)}^{2} } }[/tex]

Plug the values

⇒[tex] \mathsf{ \sqrt{( - 3 - ( - 5) )^{2} + {( - 8 - ( - 6))}^{2} } }[/tex]

When there is a ( - ) in front of an expression in parentheses, change the sign of each term in the expression

⇒[tex] \mathsf{ \sqrt{ {( - 3 + 5)}^{2} + {( - 8 + 6)}^{2} } }[/tex]

Calculate

⇒[tex] \mathsf{ \sqrt{ {(2)}^{2} + {( - 2)}^{2} } }[/tex]

Evaluate the power

⇒[tex] \mathsf{ \sqrt{4 + 4} }[/tex]

Add the numbers

⇒[tex] \mathsf{\sqrt{8} }[/tex]

Simplify the radical expression

⇒[tex] \mathsf{ \sqrt{2 \times 2 \times 2}} [/tex]

⇒[tex] \mathsf{2 \sqrt{2} }[/tex] units

Hope I helped!

Best regards!

Answer:

  25%

Step-by-step explanation:

The ratio of rise to run is ...

  rise/run = 6 ft/24 ft = 1/4

Expressed as a percentage, this is ...

  1/4 × 100% = 25%

_____

Comment on this grade

Interstate highways are limited to a 7% grade. Most local jurisdictions limit the grade of a road to somewhere between 12% and 15%.

Answer:

(-8.64) / (-0.024) = 360

Step-by-step explanation:

You have to type like this in your question;

(-8.64) / (-0.024)

or [tex]\frac{-0.024}{-8.64}[/tex].

Bye!

Answer:

  504 in³

Step-by-step explanation:

The volume of the overall outside dimensions is their product:

  Voverall = (12 in)(8 in)(6 in) = 576 in³

The volume of the "slot" is the product of its dimensions:

  Vslot = (6 in)(6 in)(2 in) = 72 in³

Then the volume of the figure shown is ...

  Vfigure = Voverall -Vslot = 576 in³ -72 in³ = 504 in³

Answer:

504 inches cubed

Step-by-step explanation:

The area missing is 6*6*2=72

The whole area is 576

subtract the two and get 504

since we are talk about volume it is 50 inches cubed

Answer:

The first one

Step-by-step explanation:

This line is the best fit for the scatter plot because it touches a lot more points than the second

Answer:

The first line

Step-by-step explanation:

Hey there!

Well the first lie is a positive slope just like the dots whereas,

the second line is a negative slope.

Therefore, the first line is the line of best fit.

Hope this helps :)

Answer:

6

Step-by-step explanation:

If a number and a variable were together in a term, the number would the the coefficient. The coefficient would multiply the variable.

In '6x', the number '6' is the coefficient. '6' would be multiplying 'x'.

The correct answer should be 6.  

Answer:

x = 180 - [(180 - 3x) + (180 - 2x)]

Step-by-step explanation:

Start off by finding the angles of the triangle

Angle F = 180 - 3x

The angle across from I (which I will call I) = 180 - 2x

Angle G = 180 - (F + I)

Now that we know what G is, we know what x is because the Alternate Exterior Angles Theorem states that if a pair of parallel lines are cut by a transversal, then the alternate exterior angles are congruent. So pretty much X = G

Therefore x =  180 - (F + I) or otherwise said as:

x = 180 - [(180 - 3x) + (180 - 2x)]

I hope this is helpful :)

Answer:

y<-8

Step-by-step explanation:

y<-1 - 7

y<-8

Answer:

y < -8

Step-by-step explanation:

To solve an inequality, we must get the variable, y, isolated on one side of the inequality.

[tex]y+7 < -1[/tex]

7 is being added to the variable, y. The inverse of addition is subtraction. Subtract 7 from both sides of the inequality.

[tex]y+7-7< -1-7[/tex]

[tex]y < -1-7[/tex]

[tex]y < -8[/tex]

The solution to the inequality is: y< -8

Answer:

You started at ( -3,5)

Step-by-step explanation:

You end at (4,5)

You got there by moving right 9 units so move left 9 units

Moving left is subtraction in the x direction

(4-9,5)

( -5,5)

Then move left 2 units so move right 2 units which is adding 2 in the x direction

( -5+2, 5)

( -3,5)

You started at ( -3,5)

Answer:

approximately 5.36

Step-by-step explanation

20 - 9.28 = 10.72

BD = EC

10.72/2 = 5.36

Answer:

2

Step-by-step explanation:

A coefficient is the number placed before the variable. The variable gets multiplied by the coefficient.

The format is not exactly clear with the expression in the question.

Assuming the expression is '8 * 2n', the coefficient would be 2.

'n' is getting multiplied by '2'.

'8' does not have a variable next to it, so it is just a term in the expression.

The product of 8 and 2 is 16. 16 is not in the expression.

If the expression was '8.2n', 8.2 would be the coefficient.

Brainilest Appreciated.

Answer:

x-axis

Step-by-step explanation:

Answer:

It is the x-axis

Step-by-step explanation:

In  a graph, the horizontal part of it is called the x axis.

Here is an definition: horizontal axis of a system of coordinates, points along which have a value of zero for all other coordinates

Answer:

sqrt of (m-7) = n+3

m = (n+3)^2 + 7 or m= n^2 + 6n + 16

sqrt of (m)-7 = n+3

m = (n+10)^2 or m =n^2 + 20n + 100

Step-by-step explanation:

(2) move the constants to the other side, and square

or  (1) square and move constants

then you can solve for m

Answer:

[tex]n^2+6n+16[/tex]

Step-by-step explanation:

I'm going to assume you meant [tex]\sqrt{m-7} = n+3[/tex], not  [tex]\sqrt{m} - 7 = n+3[/tex].

[tex](\sqrt{m-7}) ^2 = (n+3)^2\\\\(\sqrt{m-7}^2) = (n+3)^2\\\\(m-7)^{\frac{2}{2} } = (n+3)^2\\\\m - 7 = (n+3)^2\\\\m - 7 = n^2 + 2n\cdot3 + 3^2\\\\m - 7 = n^2 + 6n + 9\\\\m - 7 + 7 = n^2 + 6n + 9 + 7\\\\m = n^2 + 6n + 16[/tex]

Hope this helped!

Divide total amount used by the amount in the rate:

27,000 / 750 = 36

Multiply that number by the rate:

36 x 1.98 = 71.28

The bill is $71.28

Answer:

6×[tex]10^{-4}[/tex]

Step-by-step explanation:

Answer:

x = 69°

Step-by-step explanation:

1). JFGHI is a pentagon, every angle in a Pentagon is equal to 108°.

2). angle JIH + angle HIE = 180°; angle JIH = 108, so angle HIE = 72°.

3).  angle JDI is equal to 39° and angle IEH; so angle IEH = 39°

4). Now we know 2 out of the three angles in the triangle IHE, so we can find x!

5). x + angle HIE + angle IEH = 180°

    x + 72° + 39° = 180°

    x = 69°