I was told that 3x- was -12 but I can’t understand how they got -12:/

Answer:

D. 101

Step-by-step explanation:

(25x+1)+(25x-2)+(20x-1)+82=360

70x=360-1+2+1-82

70x=280

x=4

A=25x+1=101

Answer:

Step-by-step explanation:

find the value of a and b if 5+√3/7+2√3=a-b√3

Answer:

Your last step ( step 5 ) :

[tex] {x}^{2} + \frac{b}{a} x + \frac{ {b}^{2} }{4 {a}^{2} } = - \frac{c}{a} + \frac{ {b}^{2} }{4 {a}^{2} } [/tex]

Step 6:

[tex]{ \boxed{x + ( \frac{b}{2a}) = ± \frac{ \sqrt{ {b}^{2} - 4ac } }{ \sqrt{4a^2} } }}[/tex]

Step-by-step explanation:

[tex] {x}^{2} + \frac{b}{a} x + \frac{ {b}^{2} }{4 {a}^{2} } = - \frac{4ac}{4 {a}^{2} } + \frac{ {b}^{2} }{4 {a}^{2} } \\ \\ {x}^{2} + \frac{b}{a} x = \frac{4ac}{4a {}^{2} } \\ \\ {x} = \sqrt{ \frac{ - 4ac + b {}^{2} }{4a {}^{2} } } [/tex]

.,............. ..... ..nnkkjk

30^∘ Another boy is standing on the roof of a 10 second string be x mIn Δ ABC sin 30^∘ = AC/AB 1/2 = AC/100 AC =

Answer: hope this helps ♡

The kite was 16.9 feet high.

Step-by-step explanation:

Pythagorean theorem

b = [tex]\sqrt{c^{2} - a^{2} }[/tex]

b = [tex]\sqrt{22^{2} - 14^{2} }[/tex]

b = [tex]\sqrt{484 - 196}[/tex]

b = [tex]\sqrt{288}[/tex]

b = 16.9

Answer:

base = 18.89

legs = 16.89

Step-by-step explanation:

x + x + 68 = 180

2x + 68 = 180

2x = 112

x = 56

The altitude = 14

Tan(56) = opposite / adjacent

adjacent = base

opposite = altitude

Tan(56) = opposite / base                Multiply both sides by the base

base * Tan(56) = opposite                Divide by Tan(56)

base = opposite / Tan(56)

base = 14/tan(56)

base = 9.443

The base is actually twice this length because the altitude lands on the midpoint of the opposite side and is perpendicular to the third side (base).

base = 18.886  

Legs are the hypotenuse formed by 1/2 the base and the attitude.

Sin(56) = opposite / hypotenuse

Sin(56) = altitude / hypotenuse

hypotenuse = altitude / Sin(56)

hypotenuse = 14 / sin(56)

hypotenuse = 16.887

Rounded

base = 18.89

legs = 16.89

Answer:

a = 24.0

Step-by-step explanation:

We can use the law of sines to solve

sin 150       sin 12

---------- = ----------

a                    10

Using cross products

10 sin 150 = a sin 12

10 sin 150 / sin 12 = a

a=24.04867

To the nearest tenth

a = 24.0

Answer:

i think iys 6 lol

Step-by-step explanation:

its wright

Answer:

cos a = 12/13

tan a = 5/12

You use these properties to solve the question,

sin²a+cos²a=1

tana=sina/cosa

Answer:

The 95% confidence interval for the difference in proportion of registered voters that support this candidate between the northern and southern halves of the state is (0.05, 0.112).

Step-by-step explanation:

Before building the confidence interval, the central limit theorem and subtraction of normal variables is explained.

Central Limit Theorem

The Central Limit Theorem establishes that, for a normally distributed random variable X, with mean [tex]\mu[/tex] and standard deviation [tex]\sigma[/tex], the sampling distribution of the sample means with size n can be approximated to a normal distribution with mean [tex]\mu[/tex] and standard deviation [tex]s = \frac{\sigma}{\sqrt{n}}[/tex].

For a skewed variable, the Central Limit Theorem can also be applied, as long as n is at least 30.

For a proportion p in a sample of size n, the sampling distribution of the sample proportion will be approximately normal with mean [tex]\mu = p[/tex] and standard deviation [tex]s = \sqrt{\frac{p(1-p)}{n}}[/tex]

Subtraction between normal variables:

When two normal variables are subtracted, the mean is the difference of the means, while the standard deviation is the square root of the sum of the variances.

Northern half:

1062 out of 2000, so:

[tex]p_N = \frac{1062}{2000} = 0.531[/tex]

[tex]s_N = \sqrt{\frac{0.531*0.469}{2000}} = 0.0112[/tex]

Southern half:

900 out of 2000, so:

[tex]p_S = \frac{900}{2000} = 0.45[/tex]

[tex]s_S = \sqrt{\frac{0.45*0.55}{2000}} = 0.0111[/tex]

Distribution of the difference:

[tex]p = p_N - p_S = 0.531 - 0.45 = 0.081[/tex]

[tex]s = \sqrt{s_N^2 + s_S^2} = \sqrt{0.0112^2 + 0.0111^2} = 0.0158[/tex]

Confidence interval:

The confidence interval is:

[tex]p \pm zs[/tex]

In which

z is the z-score that has a p-value of [tex]1 - \frac{\alpha}{2}[/tex].

95% confidence level

So [tex]\alpha = 0.05[/tex], z is the value of Z that has a p-value of [tex]1 - \frac{0.05}{2} = 0.975[/tex], so [tex]Z = 1.96[/tex].

The lower bound of the interval is:

[tex]p - zs = 0.081 - 1.96*0.0158 = 0.05[/tex]

The upper bound of the interval is:

[tex]p + zs = 0.081 + 1.96*0.0158 = 0.112[/tex]

The 95% confidence interval for the difference in proportion of registered voters that support this candidate between the northern and southern halves of the state is (0.05, 0.112).

Answer:

$72

Step-by-step explanation:

The sale offers 2 pair of shoes for $45, but the price is same for 1 pair of shoes.

The cost of 3 pair of shoes

= The sale price of 2 pair of shoes + Regular price of 1 pair of shoes

= $45 + $27

= $72

So, 3 pairs of shoes will cost $72 today.

Answer:

hope this helps you

havea great dayy

Answer:

39

Step-by-step explanation:

3(6m-17)

3(30-17)

3(13)

39

Answer:

Step-by-step explanation:

[tex]\frac{\sqrt{x}+1 }{x-\sqrt{x}+1 }=\frac{\sqrt{x}+1}{(x+1)-\sqrt{x}}\\\\=\frac{(\sqrt{x}+1)([x+1]+\sqrt{x})}{([x+1]-\sqrt{x})+([x+1)+\sqrt{x}])}\\\\=\frac{\sqrt{x}*x+\sqrt{x}*1+\sqrt{x}*\sqrt{x}+1*x+1*1+1*\sqrt{x}}{(x+1)^{2}-(\sqrt{x})^{2}}\\\\\\=\frac{x\sqrt{x}+\sqrt{x}+x+1+x+\sqrt{x}}{x^{2}+2x+1-x}\\\\=\frac{x\sqrt{x}+2\sqrt{x}+2x+1}{x^{2}+x+1}\\\\[/tex]

Answer:

50%

Step-by-step explanation:

so 1 half is colored in so 1/2 is also 50%

Answer:

it's 50% because it's half the circle

Answer:

c=65

Step-by-step explanation:

Answer:

c=65

Step-by-step explanation:

c=a2+b2=63

632+162=65

Answer:

C. II only

Step-by-step explanation:

iyzgkxhldlufulduo

Answer:

Is -15

Step-by-step explanation:

Isolate the variable by dividing each side by factors that don't contain the variable.

x  =  1

-6+3x+4=2-4x+3

-8+7x+1=0

7x=7

x=1

Answer:

x=1

Step-by-step explanation:

SEE IMAGE for Solution

Answer:

please mark me brainlist I really need it

Step-by-step explanation:

Say the height of the room is X metres. So the length is 3X, and the breadth is length/2, or 3X/2.

The area of the 4 walls is then 3x^2 + 3X^2 + 3X^2/2 +3X^2/2 = 9X^2

If the cost of plastering is R5/sq m, then 9X^2 * 5 = 720

Solving this gives X = 4 m - a rather high ceiling

The floor area is then (3*4) * (3*4/2) = 72 sq m

Carpeting is then 250*72 = R18000

Answer:

10

Step-by-step explanation:

(10*2) ÷ (1+1)

Parentheses first

20 ÷2

Then divide

10

Answer:

The answer to the equation is 10.

Step-by-step explanation:

Use PEMDAS/Order of operations.

Parentheses go first.

(10*2) divided by (1+1)

remove the parentheses after working on the equation in them

20 divided by 2

20/2=10

the answer is 10

If you have any questions tell me them in the comments, I will come answer them. Have a good day.

Answer: x = 1 hour and 33 minutes

Step-by-step explanation:

Let x = time (hours) it takes typing together

then

x(1/2 + 1/7) = 1

 multiplying both sides by 14:

x(7 + 2) = 14

x(9) = 14

x = 14/9

x = 1.56 hours

or

x = 1 hour and 33 minutes

Hope tjis help you!:)

Answer: 14/9 hr

Step-by-step explanation:

If you divide Frank's ability to write 1 report by 2 hours, he could write half a report in an hour. James could write one seventh of the report in a hour after dividing his ability to write 1 report in 7 hours. Find the least common denominator between 2 and 7, which is 14 convert 1/2 to that, which would be 7/14 and 2/14. Add That together and you'd get the amount of report they can write in an hour. If you multiply this by a number equalvilent to flipping 9/14, you'd get 1. This number is 14/9 hours.

Answer:

72 sq cm

Step-by-step explanation:

Surface area of the cuboid is 2*(lb+bh+lh)=2*(12+18+6)=2*36=72

Answer:

36 sq cm

Step-by-step explanation:

This prism is formed by rectangles, and to find the area of a rectangle you have to multiply its sides. So, to find the surface area, you find the area of each rectangle and after add it all:

3×2 = 6 sq cm, and your have two of this rectangles

6×2 = 12 sq cm, and you also have two of this

3×6 = 18 sq cm, and also have two of this

6 + 12 + 18 = 36 sq cm

Answer:

40 degrees

Step-by-step explanation:

Supplementary angles are a pair of angles that add up to 180 degrees

Since ABD and DBC are supplementary, you can make the equation:

180=140+x

Simplify and you get x=40

[tex]\bf \large \implies \: \: x \: + \: 140 \degree \: = \: 180 \degree[/tex]

[tex]\bf \large \implies \: \: x \: = \: 180 \degree - \: 140 \degree[/tex]

[tex]\bf \large \implies \: \: x \: = \: 40 \degree[/tex]

Answer:

1

Step-by-step explanation:

16-9=5t+2t

7=7t

1=t

Answer:

t = 1

Step-by-step explanation:

16 - 2t = 5t + 9

=> 16 - 2t - 9 = 5t

=> 16 - 9 = 5t + 2t

=> 7 = 7t

=> 7/7 = t

=> 1/1 = t

=> 1 = t

Answer:

the answer is 100:60:40 hope it helps

Answer:

so the simplest way to find the volume of water is by dividing into different....objects

so when dividing you create a rectangular box that has length of 12 width of 14.5 and height of 5 and another rectangular box with length of 7 (19-12) width of 4 and height of 5

now calculate the volume of each box and add them up

v = length x width x height

box 1 = 12 x 14.5 x 5 = 870 ft^3

box 2 = 7x4x5 = 140

now smash them up together = 870+140=1010ft^3

hope that answers your question

Answer:

$879.190 = $879.19

$532.626 = $532.627

Step-by-step explanation:

You round up for the tenths place if the hundredths place is above five, but you round down for the tenths place if the hundredths place is below five. For example, 0 is below five for $879.190, so I round to 9.

Answer:

[tex] \sin(120) \\ = \sin(90 + 30) \\ = \cos(30) \\ = \frac{ \sqrt{3} }{2} \\ \\ \tan( \frac{3\pi}{4} ) \\ = \tan(135) \\ = \tan(90 + 45) \\ = - \cot(45) \\ = - 1[/tex]

[tex]\\ \rm\longmapsto sin120[/tex]

[tex]\\ \rm\longmapsto sin(90+30)[/tex]

[tex]\\ \rm\longmapsto cos30[/tex]

[tex]\\ \rm\longmapsto \dfrac{\sqrt{3}}{2}[/tex]

Now

[tex]\\ \rm\longmapsto tan\left(\dfrac{2\pi}{4}\right)[/tex]

[tex]\\ \rm\longmapsto tan135[/tex]

[tex]\\ \rm\longmapsto -1[/tex]

Answer:

below

Step-by-step explanation:

In short, we will add both coefficients together to combine like terms.

3x + 5x → x(3 + 5) → 8x

If you have a value like 2x and 2, you cannot combine them because they do not have the same variable.

Best of Luck!

9514 1404 393

Answer:

  after 89 years

Step-by-step explanation:

For principal p, interest rate r, and number of years t, the two account balances are ...

  a = p·e^(rt) . . . . continuous compounding

  a = p(1+r)^t . . . . annual compounding

Using the given values, we have

  3000·e^(0.07t) . . . . . compounded continuously

  20000·1.05^t . . . . . . compounded annually

We want to find t so these are equal.

  3000·e^(0.07t) = 20000·1.05^t

  0.15e^(0.07t) = 1.05^t . . . . divide by 20,000

  ln(0.15) +0.07t = t·ln(1.05) . . . . take natural logarithms

  ln(0.15) = t·(ln(1.05) -0.07) . . . . subtract 0.07t

  t = ln(0.15)/(ln(1.05) -0.07) ≈ -1.8971/-0.02121 . . . . . divide by the coefficient of t

  t ≈ 89.4 ≈ 89

The two accounts will have the same balance after 89 years.