The sum of the digits of a certain two-digit number is 7. Reversing its digits increases the number by 9. What is the number?

Answer:  \frac{2}{5}  ; or, write in decimal form:  0.4 .

Step-by-step explanation:

Rewrite as:

_______________________

    [tex]\frac{4x}{7} = \frac{8}{35}[/tex] ;

________________________

Now, "Cross-factor multiply":

that is:

_____________________

 → Given:   [tex]\frac{a}{b} =\frac{c}{d}[/tex]  ;

    → ad = bc ;  (b≠0 ; d≠0) ;

_____________________

As such:

 4x * 35 = 7 * 8 ;

_______________________

We can divide one side of the equatiuon by "4" ; and one side by "7" :

  [tex]\frac{4x*35}{4*7} = \frac{7*8}{4*7}[/tex] ;

_______________________

We can simplify the "left-hand side":

 "4/4 = 1 " ; and "35/7 = 5 " ; & we are left with "x * 5" ; or "5x " .

________________________

We can simplify the "right-hand side":

 "7/7 = 1 " ; and: "8/4 =2 " ; to get: "2/1" ; which equals "2".

_________________________

So; we have:  " 5x = 2 " ; Solve for "x" ;

__________________________

  Divide each side of the equation by "5" ; to isolate "x" on one ide of the equation; & to solve for: "x" ;

__________________________

  " 5x/5 = 2/5 " ;  We cancel out the "5x/5" to "1x"; which equals "x":

    → x = [tex]\frac{2}{5}[/tex]  ;  or, write in decimal format:  "x = 0.4" ;

___________________________

\frac{2}{5}

____________________________

Hope this is helpful!  Best wishes in your academic pursuits—and within the "Brainly" community!

____________________________

Answer:

[tex]x = 0.4[/tex]

Step-by-step explanation:

[tex]\frac{7}{4} x \frac{4}{7} = \frac{7}{4} x \frac{8}{35}[/tex]

Reduce the number with the greatest common factor 7

[tex]\frac{1}{4} x 4x= \frac{7}{4}x\frac{8}{35}[/tex]

[tex]x=\frac{7}{4}x\frac{8}{35}[/tex]

[tex]x=7x\frac{2}{35}[/tex]

[tex]x=\frac{2}{5}[/tex]

Answer:

A= -8

Step-by-step explanation:

Subtract 5a from both sides.

Combine 4a and −5a to get −a.

Add 7 to both sides.

Finally, Multiply both sides by −1.

Pls mark brainliest.

Answer:

a = -8

Step-by-step explanation:

4a - 7 = 5a + 1

subtract 1 from both sides of the equation

4a - 7 - 1 = 5a + 1 - 1

4a - 7 - 1 = 5a

4a - 8 = 5a

subtract 4a from both sides of the equation

4a - 4a - 8 = 5a - 4a

-8 = 5a - 4a

-8 = 1a

-8 = a

Answer:

Not sure what you wanted but here Divide each term by

−

5

-

5

and simplify.

Exact Form:

k

=

−

12

5

k

=

-

12

5

Decimal Form:

k

=

−

2.4

k

=

-

2.4

Mixed Number Form:

k

=

−

2

2

5

Step-by-step explanation:

Answer:

k= -2.4

Step-by-step explanation:

Answer:

Step-by-step explanation:

131.95

The volume of cylinder and cone are [tex]36\pi[/tex] cubic unit.

It is given by formula, [tex]V=\pi r^{2}h[/tex]

Where r is base radius and h is height of cylinder.

Given that,  [tex]r=3,h=4[/tex]

Substitute values in above formula,

         [tex]V=\pi*3^{2} *4=36\pi[/tex]

Volume of the cone is,

                 [tex]V=\frac{1}{3} \pi r^{2}h[/tex]

Given that, [tex]r=3,h=3*4=12[/tex]

Substitute values in above formula.

    [tex]V=\frac{1}{3}\pi*3^{2}*12=36\pi[/tex]

Learn more about the volume of cylinder here:

https://brainly.com/question/9554871

Answer: 6,-6

Step-by-step explanation:

Because when you add the same number and one of them is a negative it will always be a zero. For example: (-2+2)= 0

I'm sorry if this didn't help.

Answer: b = 9

Step-by-step explanation:

Set up proportions.

20 : 12

15 : b

Cross multiply the proportions.

20b : 180

Simplyfi the ratio.

20b/20

180/20

The answer is b = 9.

hope this helps :)

Answer:

Step-by-step explanation:

15    b

20  12

15 times 12 is 180

20 times b is 20b

20b=180

÷20  ÷20

b=9

9/12=15/20

3/4=3/4

Answer:

Number 1 is also 125 because it corresponds.

Step-by-step explanation:you see other line in the triangle right!if u see both are giving that line anywhere then you will know they corresponds! hope it hels!good night!

Answer:

C

Step-by-step explanation:

think of a random K number (like 3 for example)

1/2(3) = 3/2

this equals k/2 = 3/2

Answer:

A. [tex]f(x)= \frac{1}{2}^x[/tex]

D. The domains of both functions are the same

E. The translation between [tex]f(x)[/tex] to [tex]g(x)[/tex] right 4 units and down 2 units.

Answer:

(5x-8)(x-2)

Step-by-step explanation:

or either use quadratic formula

Answer:

5(1+x)

Step-by-step explanation:

Answer:

Sarah: £15

Fiona: £15

David: £10

Step-by-step explanation:

3 + 3 + 2 = 8

40 ÷ 8 = 5

3 × 5 = 15

3 × 5 = 15

2 × 5 = 10

Answer:

YZ = 12

Step-by-step explanation:

From the question given above, the following data were obtained:

Length of XZ = 13

Lenght of XY = 5

Lenght of YZ =?

The length of YZ can be obtained by using pythagoras theory since the figure is a right angle triangle. This can be obtained as follow:

XZ² = XY² + YZ²

13² = 5² + YZ²

169 = 25 + YZ²

Collect like terms

169 – 25 = YZ²

144 = YZ²

Take the square root of both side.

YZ = √144

YZ = 12

Therefore, the length of YZ is 12

Answer:

x=5

Step-by-step explanation:

2x-3(3x-11)= -2

2x-9x+33= -2

-7x-33= -2

-7x= -33-2

-7x= -35

÷ -7= ÷ -7

x= 5

Answer:

x = 11

Step-by-step explanation:

3(x-5) = 18

Step one: Distrubute 3 to the numbers in the parenthesis.

3x - 15 = 18

Step two: Add 15 on both sides

3x = 33

Step three: Divide by 3 on both sides

x = 11

Answer:

Area of B =80

I hope it's helps you

Answer in interval notation is  (-3, 1)

This is the same as saying -3 < x < 1

=====================================================

Explanation:

Since y = f(x), this means we're looking for points on the red curve such that they have a negative y coordinate. Visually, we're looking for points that are below the horizontal x axis.

These points are shown in the diagram below. I've marked the section we're after in blue. This blue section spans from x = -3 to x = 1. We exclude both endpoints because each x value leads to f(x) = 0, but we want f(x) values smaller than zero.

Answer:

Its the second option

Step-by-step explanation:

The value of midpoint of AC will be 0.5.

Number line is a horizontal line where numbers are marked at equal intervals one after another form smaller to greater.

Given that;

Point A is at - 2 and C is at 3 on the number line.

Now,

Since, Point A is at - 2 and C is at 3 on the number line.

Hence, The midpoint of AC = (- 2 + 3 ) / 2

                                           = 1/2

                                           = 0.5

Thus, The midpoint of AC = 0.5

Learn more about the number line visit:

https://brainly.com/question/13088605

#SPJ2

Answer:

it is a not a function

Step-by-step explanation:

if you times 51 that's a hundred

Answer:

25

Step-by-step explanation:

An unknown number of people signed up for the class. Let the total number of people who signed up be x.

56% of the people who signed up are beginners. 14 people are beginners.

That means that

56% of the people who signed up is 14 people.

56% of x = 14

56% * x = 14

0.56x = 14

Divide both sides by 0.56.

0.56x/0.56 = 14/0.56

x = 25

Answer: 25

Answer:

well I'm not sure which way u want me to go so i'll do both ways

-31 orr if your going the other way, -45

Answer:

10cm

Step-by-step explanation:

CDB and CEA are similar=>CD/CE=DB/EA=>5/9=DB/18=>

9DB=90

DB=10

The required length of DB in the diagram below is 10 cm.

Triangle is a polygon that has three sides and three angles. The sum of the angle of the triangle is 180 degrees.

Given:

In the given triangle we have

СD=5 cm

DE= 4 cm

EA= 18 cm

According to given question we have

In a triangle CDB and CEA are similar

So,

[tex]\frac{CD}{CE} =\frac{DB}{EA}\\\\=\frac{5}{9} =\frac{DB}{18}\\\\=9DB=90\\\\DB=10[/tex]

Therefore, the required length of DB in the diagram below is 10 cm.

Learn more details about triangle here:

https://brainly.com/question/2773823

#SPJ5

Answer:

Yes, that is correct. Congrats 7 year old.

Step-by-step explanation:

2 plus 2 equals 4

:)

thanks for points

Answer:

580 seedlings altogether.

Step-by-step explanation:

Given that,

Ali plants 40% of the total number of seedlings, Ben plants 45% of the total number of seedlings, and Cliff plants the rest of the seedlings. Cliff plants 87 seedlings.

The percentage of the seedling planted by Cliff = 100% - 45% - 40% = 15%

Let x = the total number of seedlings

[tex]15\%\ of\ x=87\\\\x=\dfrac{87\times 100}{15}\\\\x=580[/tex]

Hence, three boys plant 580 seedlings altogether.

Answer:

slope = 2/3

Step-by-step explanation:

Answer & Step-by-step explanation:

You can check your answer easily by using inverse operations. For example, if you're solving for 1+2, you can check it by subtraction. Since 1+2=3, you can subtract 3 by 1, and you come up with 2.

Hope this helps and have a nice day (～￣▽￣)～