Twice a number decreased by 39 is five times the sum of the
number and 2 times the number. Find the number.

Answer:

16

Step-by-step explanation:

the quadratic equation –3 = –x2 + 2x can be changed into :

x²-2x-3= 0

a=1, b= -2 , and c = -3

so, the discriminant = (-2)²-4(1)(-3)

= 4 + 12 = 16

Answer:

a) 30

b)600pi

Step-by-step explanation:

For the first questions, since the arc is 240°, the area of the sector and circumference will be 240/360 or 2/3 of the total of the circles'. Therefore 125.6 x 3/2 is the circumference, which is 188.4. When we divide this by 6.28, we get 30

Now, since the area is pi r^2 where we know that r=30, we get 900pi as the area of the whole thing, however since the sector is 2/3 of the whole circle, 2/3 x 900pi = 600pi

Answer:

I think the answer is 10 hours

the 11.95 seems wrong

Step-by-step explanation:

[tex]\frac{1}{6} + \frac{1}{y} = \frac{1}{3.75}[/tex]

multiply by 22.5 y

3.75 y + 22.5 = 6y

y = 10

Answer:  True

Explanation:

Consider a 3D cardboard box that you can unfold. It would unfold into a 2D net that you can then re-fold back into its 3D form. The 2D net is useful to help visualize and calculate the surface area. The surface area is simply the total area of all the external faces.

The only 2-digit number that is lesser than 50 and the sum of its digits remain unaffected despite being multiplied by a number < 1 would be '18.'

To prove, we will look at some situations:

If we add up the two digits of 18. We get,

[tex]1 + 8 = 9[/tex]

And we multiply 18 by 2 which is greater than 1. We get,

[tex]18[/tex] × [tex]2 = 36[/tex]

The sum remains the same i.e. [tex]3 + 6 = 9[/tex]

Similarly,

If 18 is multiplied to 3(greater than 1), the sum of the two digits comprising the number still remains the same;

[tex]18[/tex] × [tex]3 = 54[/tex]

where (5 + 4 = 9)

Once more,

Even if 18 is multiplied to 4 or 5(greater than 1), the sum of its digits will still be 9.

 [tex]18[/tex] × [tex]4 = 72[/tex]

[tex](7 + 2 = 9)[/tex]

[tex]18[/tex] × [tex]5 = 90[/tex]

[tex](9 + 0 = 9)[/tex]

Thus, 18 is the answer.

Learn more about 'numbers' here: brainly.com/question/1624562

Answer:

hope this help

Step-by-step explanation:

Answer:

90

51

10

Step-by-step explanation:

Answer:

x=-8

Step-by-step explanation:

4(1/2x+7)=12

Divide each side by 4

4/4(1/2x+7)=12/4

(1/2x+7)=3

Subtract 7 from each side

1/2x+7-7=3-7

1/2x = -4

Multiply each side by 2

1/2x*2 = -4*2

x = -8

Answer:

-8

Step-by-step explanation:

Divide both sides by 4 which will give you 1/2x+7=3

Then multipy both sides by 2 which will then give you x+14=16

Then move the constant = x=6-14

6-14 is -8 which will give you x=-8

Answer:

[tex] \frac{1}{6} [/tex]

Step-by-step explanation:

[tex] \frac{7}{5} \times \frac{5}{12} - \frac{3}{12} \times \frac{7}{5} - \frac{1}{15} = \frac{7}{5} ( \frac{5}{12} - \frac{3}{12} ) - \frac{1}{15} = \frac{7}{5} \times \frac{1}{6} - \frac{1}{15} = \frac{7}{30} - \frac{2}{30} = \frac{5}{30} = \frac{1}{6} [/tex]

Answer:

[tex]Expected = 0.09375[/tex]

Step-by-step explanation:

Given

[tex]Balls = 4[/tex]

[tex]n = 4[/tex] --- selection

Required

The expected distinct colored balls

The probability of selecting one of the 4 balls is:

[tex]P = \frac{1}{4}[/tex]

The probability of selecting different balls in each selection is:

[tex]Pr = (\frac{1}{4})^n[/tex]

Substitute 4 for n

[tex]Pr = (\frac{1}{4})^4[/tex]

[tex]Pr = \frac{1}{256}[/tex]

The number of arrangement of the 4 balls is:

[tex]Arrangement = 4![/tex]

So, we have:

[tex]Arrangement = 4*3*2*1[/tex]

[tex]Arrangement = 24[/tex]

The expected number of distinct color is:

[tex]Expected = Arrangement * Pr[/tex]

[tex]Expected = 24 * \frac{1}{256}[/tex]

[tex]Expected = \frac{3}{32}[/tex]

[tex]Expected = 0.09375[/tex]

Answer:

Step-by-step explanation:

from the picture:

QP = QR

and

QR = RS

so

PQ + RS = QS

Answer:

C.

0.5; 13.5; 1093.5

Step-by-step explanation:

Answer:

L={∅}

Step-by-step explanation:

Answer:

≈ 0.19

Step-by-step explanation:

So first, we find the probability of getting 1 yellow marble (the formula is the number of amount of type over the total number of items), which is:

10/(6+10+5+1)

= 10/22

= 5/11.

So getting a yellow marble on the first try is 5/11 likeliness.

Now, for the second one, we do the same except that you are NOT putting it back into the bag, which means we have to subtract the yellow marble you already took AND ALSO ONE FROM THE TOTAL AMOUNT OF YELLOW MARBLES.

To find the probability of getting the second marble, our equation is:

9/(6+9+5+1)

= 9/21

= 3/7.

Lastly, to find the probability of getting them both consecutively, we multiply the two results.

5/11 * 3/7

= 15/77

≈ 0.19

I hope this helped! :D

9 in 8956 = 900

9 in 95675 = 90000

9 = 9 in 124569

9 in 68795 = 90

90000 = 9 in 2549652.........

hope it helps...

Answer:

Option B

a(n) = 8 + (n-1) • 6

Answered by GAUTHMATH

Answer:

here's the answer to your question

Answer:

D) 40

Step-by-step explanation:

To solve the question you can use the knowledge that every triangle has a total of 180 degrees. Two of the angles are known one is 50 and the other is 90. We know one is 90 because of the square around the angle. Then, you can set up an algebraic equation to solve. We know that 50+90+x=180, so solve for x for the final answer of 40.

The image of this question is missing and so i have attached it.

Answer:

dd/dt = 4.47 ft/s

Step-by-step explanation:

From the image attached, let's denote the following;

d = horizontal distance beneath pulley

h = height of pulley

l = diagonal from the pulley to the head of the person

v = velocity of rope rising

Using pythagoras theorem;

l² = d² + h²

Differentiating with respect to time and considering h = c^(te) gives;

2l(dl/dt) = 2d(dd/dt)

We are given;

d = 20 ft

h = 10 ft

v = 4 ft/s

We know that velocity in this case is change in diagonal distance with time. Thus;

v = dl/dt = 4 ft/s

From earlier, we saw that;

2l(dl/dt) = 2d(dd/dt)

Thus, reducing it gives

(dl/dt)(l/d) = dd/dt

Now, l² = d² + h²

l = √(d² + h²)

Also, v = dl/dt = 4

Thus;

4(√(d² + h²))/d = dd/dt

4(√(20² + 10²))/20 = dd/dt

dd/dt = 4.47 ft/s

let the n'th term be called x, and the value of the term y,

then there is a function y=a*x + b

that will give us all term we want.

this formula is also used for straight lines.

we just need a and b. we already got two data points. we can just plug the known x/y pairs into the formula

10.5 = a*12 + b

13.5 = a*18 + b

now lets manipulate these lines.

multiply the first line by 3 and the second line by 2

31.5 = a*36 + 3b

27 = a*36 + 2b

subtract the second line from the first line

4.5 = b

yey, we now know b, let's plus b into either line from above, I'll go with the first one, looks easier.

10.5 = a*12 + 4.5

6 = a*12

0.5 = a

now y=a*x + b can be filled with a and b

y = 0.5 * x + 4.5

for x=1 (the first term) it's f(1)=5

each step is 0.5, hence the common difference.

(13.5-10.5)/(18-12)

= 3 / 6

= 0.5

we got the comment difference by looking at the full difference over 6 steps and divined by these 6 steps.

from step 12 to step one it's 11 steps down

10.5 - 0.5*11

= 10.5 - 5.5

= 5

Answer:

7x and 2x. 3x^2 and -7x^2.

Step-by-step explanation:

7x and 2x both have x. 3x^2 and -7x^2 both have x^2.

Answer:

Step-by-step explanation:

Choice A is the only one that is applicable.

Answer:

A. F(x) has 1 relative minimum and maximum.

Step-by-step explanation:

[tex]{ \bf{F(x) = 2 {x}^{3} - 2 {x}^{2} + 1 }}[/tex]

As x and F(x) tend to positive and negative infinity:

[tex]{ \sf{x→ \infin : f(x) = \infin}} \\ { \sf{x→ {}^{ - } \infin : f(x) → {}^{ - } \infin}}[/tex]

❎So, B and C are excluded.

Roots of the polynomial:

[tex]{ \sf{f(x) = 2 {x}^{3} - 2 {x}^{2} + 1}} \\ { \sf{f(x) = - 0.6 \: \: and \: \: 0.8}}[/tex]

❎, D is also excluded.

✔, A

The line was reflected about the line y = -x.

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

This question is solved using reflection concepts.

There are various kinds of reflections, 90º clockwise about the origin, 90º counterclockwise, among other, and each of them has a rule.

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

In this question:

From this, we have the following rule: (x,y) -> (-y,-x)

Checking the rules, it can be said that the line was reflected about the line y = -x.

A similar question can be found at https://brainly.com/question/16130908

Answer:

x = 155º

Step-by-step explanation:

y = 25°    {Vertically opposite angles}

x + y = 180    {Co-interior angles are supplementary}

x + 25 = 180

Subtract 25 from both sides

x = 180 - 25

x = 155°

Answer: [tex]\dfrac{8}{3}\ m[/tex]

Step-by-step explanation:

Given

Length of the plank is [tex]6\ m[/tex]

Foot of the flank is [tex]4\ m[/tex] away from the wall

Lizard climbs 2 m up the wall

from the figure, the two triangles are similar

[tex]\therefore \dfrac{2}{6}=\dfrac{x}{4}\\\\\Rightarrow x=4\times \dfrac{2}{6}\\\\\Rightarrow x=\dfrac{4}{3}\ m[/tex]

So, the distance from the wall is

[tex]\Rightarrow 4-x\\\\\Rightarrow 4-\dfrac{4}{3}\\\\\Rightarrow \dfrac{8}{3}\ m[/tex]

Add the ratio: 3 + 5 = 8

Divide total students by that:

32/8 = 4

The ratio for girls is 3, multiply the 4 by 3:

4 x 3 = 12

There are 12 girls

Answer:

12

Step-by-step explanation:

If the ratio of girls to boys is 3:5, that means that for every 8 total students, 3 would be girls and 5 would be boys. Therefore 3/8 of the students are girls and 5/8 are boys. If 3/8 are girls, then:

[tex]\frac{3}{8}[/tex] of 32

= [tex]\frac{3}{8} * 32[/tex]

[tex]=\frac{3 * 32}{8} \\= \frac{96}{8} \\= 12[/tex]

There are 12 girls.

Answer:

$61.50

Step-by-step explanation:

14.25(4) + 4.50

= 57.00 + 4.50

= 61.50

Answer:

not sure if the answer is obvious but I'd say $6.89 + t = $8.00

Step-by-step explanation:

so to make it more understandable you have to first go over the question and ask your self is the tip included in the totally amount owed or is it apart

after you figure out that its apart all you have to do is plug in the numbers you could verify this by checking every equation like this

$6.89 + t = $8.00 (t) in this case is the tip which would be $1.11 all you do to arrive at that answer is subtract the amout owed from the amount given like this $8.00 - $6.89 = $1.11 which will be your tip

now continue checking your answer next is , $6.89 - t = $8.00

which would be $6.89- $1.11 = $5.78 not quite right because now she is short on the pay , on to the next its $6.89t= $8.00 which would be $6.89 x $1.11= $7.65 rounded to neartest tenth which would included the amount but not all the tip given meaning tip would be short 0.35 cents and finally $6.89= $8.00 divided by t , now this takes the amount give which is $8.00 and divides by t which is $1.11 doing this $6.89 = $8.00/$1.11 which it is trying to imply that $6.89 is equal to $7.21 which would be incorrect making the only reasonable equation $6.89 + t = $8.00 reaveling that the tip given was $1.11

hopefully that help maybe i can get brainlist?!

Answer:

6.89 + t = 8.00

Step-by-step explanation:

it's A

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