Tính nhẩm:
a, 138^2-38^2 b, (10^2+8^2+6^2+4^2+2^2)- (9^2+7^2+5^2+3^2+1^2)
PLZZZ, giúp vs

I think you tried copy pasting the thing in here. usually written equations on tests or whatever don't copy paste well

Answer:not a man but I think you should just relax and be yourself, high school isn’t scary at all. When you go in for orientation walk around the school and find your classes so you have a good map of where you need to go in your head already! Best of luck

Step-by-step explanation:

Answer:

8 cm

Step-by-step explanation:

The length of the whole shape is 13. On the right side, it says the length is 5 cm. You use 13-5 to get the missing length.

Answer:

the answer is 8 cm

Step-by-step explanation:

Answer:

Quelles caractéristiques ces mots ont-ils en commun ? Cliquez sur tout ce qui s'applique.

Step-by-step explanation:

Answer:

Eldrick can use both of these samples to find the mean frequency of each duck.

Step-by-step explanation:

Given

See attachment for samples

Required

Determine which is true

Reading through the options, we can see that Eldrick needs to evaluate the mean frequency of both samples.

To do this, both samples have to be put into consideration in order to arrive at the right value.

Considering the options, we can conclude that (a) is correct.

Answer:

B

Step-by-step explanation:

the answer is B cause I did A and it was wrong trust me, and have a good day

Answer:

(I'll leave cm out to save space and time in the answer)

the perimeter is 500, there are 5 sides. so on average a side will be 100.

that's already the important key idea.

it's indeed 100 for the third side, the second will be 10 less, the fourth 10 more (making the 2and and the 4th side 200 in sum, and therefore still 100 on average).

repeat this for the 1. and 5. side and we get:

80

90

100

110

120

Answer:

35/9

Step-by-step explanation:

7y=-3x-1

y=-3/7x-1/7

m=-3/7

Now,

3my=-5x+2

y=-5/3mx+2/3

So

-3/7=-5/3m

-9m=-35

m=35/9

Answer:

35/9

Step-by-step explanation:

What we need to know:

Parallel lines have the same slope

slope intercept form: y = mx + b

m = slope

The first thing we will want to do is put both equations in slope intercept form.

We must do this so we can identify the slope.

First equation:

3x + 7y + 1 = 0

Solve for y

Subtract 1 from both sides

3x + 7y + 1 - 1 = 0 - 1.

3x + 7y = -1

Subtract 3x from both sides

3x - 3x + 7y = -1 - 3x

7y = -3x - 1

Divide both sides by 7

7y/7 = (-3x - 1)/7

y = -3/7x - 1/7

So the equation of the first line is y = -3/7x - 1/7

Second equation:

5x + 3my – 2 = 0

Solve for y

Subtract 5x from both sides

5x - 5x + 3my - 2 = 0 - 5x

3my - 2 = -5x

Add 2 to both sides

3my - 2 + 2 = -5x + 2

3my = -5x + 2

Divide both sides by 3m

3my/3m = (-5x + 2)/3m

y = -5x/3m + 2/3m

So the equation of the second line is y = -5x/3m + 2/3m

So we have the two equations:

y = -3/7x - 1/7 and y = -5x/3m + 2/3m and we want to find the value of m if the two lines are parallel

Lines that are parallel have similar slopes

So the slope of the first equation should be the same as the slope of the second equation

The slope of y = -3/7x - 1/7 is -3/7 as it takes the spot of "m" in y = mx + b.

The slope of y = -5x/3m + 2/3m is -5/3m as it takes the spot of "m"

If the slopes of parallel lines must be similar than -3/7 = -5/3m

(Note that we've just created an equation that we can use to solve for m)

We now solve for m

-3/7 = -5/3m

Cross multiply

3*-3m = -9m

7*-5=-35

we acquire -35 = -9m

Divide both sides by -9

-35/-9 = 35/9

-9m/-9=

We're left with m = 35/9

So we can conclude that the value of m would be 35/9 if the two lines are parallel

Answer:

x = 14.0902 (After rounding to the nearest ten-thousandth)

Step-by-step explanation:

Using the bottom angle to solve x, the best option to use would be sine as we have the length for the opposite leg. Then we do the following:

Sin(69) = Opp/Hyp

Sin(69) = 14/x

0.9336 = 14/x

0.9336(x) = 14/x(x)

0.9336x = 14

0.9336x/0.9336 = 14/0.9936

x = 14.0902

Answer:

x2 + 10x +25 = (x+5)^2

Step-by-step explanation:

x^2 + 10x

To complete the square

Take the coefficient of x

10

Divide by 2

10/2 =5

Square it

5^2 =25

Add it

x2 + 10x +25

The coefficient of x divided by 2 is the factor we add to x inside the square

(x+5)^2

Answer:

25 should go in the blank.

Step-by-step explanation:

You can factor and get (x + 5)^2, a perfect square trinomial when put into standard form.

Answer:

cost price of book is Rs. 570

Answer:

V = 5,324 in^3

Step-by-step explanation:

V = 4([tex]\pi[/tex]r^3)/3

= 4(3)(11^3)/3

= 12(11)(11)(11)/3

= 12(1,331)/3

= 15,972/3

V = 5,324 in^3

Answer:

5575.28 or 5,324 depending on use of pie.

Step-by-step explanation

V=4/3πr3=4/3·π·113≈5575.27976

Hope this helps :)!

This is the answer if pie is used as 3.14.

V = 5,324 in^3 if pie used as 3.

V = 5575.28 in^3 if pie used as 3.14.

Answer: The Answer IS Either Letter B Or Letter C

B.

an=100 · (12)n−1a subscript n baseline equals 100 times left parenthesis one half right parenthesis superscript n minus 1 baseline

Step-by-step explanation: I Think The Answer IS Letter B

Simplify the matrix.

a = 100 ,

a n = 12 a n − a ,

1 ,

100 ,

n , − h a l f ,

n ,

1

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

Phase shift and period change

Rewriting the equation:

y = cos ( 2 ( x - 2 ) )

Phase shift 2 units to the right

Period changed to 2pi/2 = pi

Answer:

5.1

Step-by-step explanation:

ik i am in the future

Answer:

the answer is correct

Step-by-step explanation:

hope u like

Answer:

please i need educere answers

Step-by-step explanation:

i have one day left and i cannot finish please reply with any way to contact you

Answer:

60⁰

Step-by-step explanation:

A triangle has three angles.

The sum of its angles = 180⁰

[ By angle sum property ]

Let the unknown angle be 'x'

Then,

30⁰ + 90⁰ + x = 180⁰

120⁰ + x = 180⁰

x = 180⁰ - 120⁰

x = 60⁰

Therefore, the unknown angle will be equal to 60⁰

Answer:

Step-by-step explanation:

Answer:

60 (E)

Step-by-step explanation:

He plants seeds -> plants grow to 12 times the original weight of the seeds -> he sells 50 tonnes from the harvest -> remainder is used as the next batch of seeds

He harvested 120 tonnes this year which means the original weight of the seeds planted was 120÷12 = 10 tonnes. This means that last years harvest would be the 10 tonnes used as seeds plus the 50 tonnes that would have been sold immediately, 10+50 = 60 tonnes

Given:

The function [tex]g(x)[/tex] doubles the square of the input and then subtracts 13.

To find:

The value of [tex]g(3)[/tex].

Solution:

Let [tex]x[/tex] be the input value.

The square of the input is [tex]x^2[/tex].

Doubles the square of the input [tex]2x^2[/tex].

Doubles the square of the input and then subtracts 13, i.e., [tex]2x^2-13[/tex].

So, the function is:

[tex]g(x)=2x^2-13[/tex]

Putting [tex]x=3[/tex] in the above function, we get

[tex]g(3)=2(3)^2-13[/tex]

[tex]g(3)=2(9)-13[/tex]

[tex]g(3)=18-13[/tex]

[tex]g(3)=5[/tex]

Therefore, the value of [tex]g(3)[/tex] is 5.

Answer: x³-21x+20=0

Step-by-step explanation:

To find which polynomial has 1, 4, -5 as the roots, all we have to do is equal each root to 0 and multiply all factors together.

1 is (x-1)=0

4 is (x-4)=0

-5 is (x+5)=0

Now, we just multiply them together.

(x-1)(x-4)(x+5)=0                       [FOIL]

(x²-4x-x+4)(x+5)=0                    [combine like terms]

(x²-5x+4)(x+5)=0                      [FOIL]

x³+5x²-5x²-25x+4x+20=0       [combine like terms]

x³-21x+20=0

Now we know x³-21x+20=0 is the polynomial with those roots.

Answer:

B, pi

Step-by-step explanation:

The sine wave shown above has two waves until it reaches 2 pi, making the period of the sine graph 2pi divided by the two waves, making the answer pi.

Answer: A

Step-by-step explanation:

Using the distributive property, for the denominators, you get x^2+4x-5x-20. Combining like terms, 4x-5x is -1x. So x^2-x-20. -1x is the equivalent to -x because -1*x is -x. There is only one solution with this denominator, A. So there’s no need to figure out the numerator.

Answer:

x= п/2+пn; nE Z    

x= п/6+пn; nEZ

Step-by-step explanation:

(cosx)^2- √3sinxcosx=0

Factorise it

cosx(cosx-√3sinx)=0

cosx=0                     or                      cosx=√3sinx

x= п/2+пn; nE Z                                 cosx/cosx= √3sinx/cosx

                                                          1/√3= tgx

                                                           x= arctg 1/√3+пn; nE Z

                                                            x= п/6+пn; nEZ

The answer is x= п/2+пn; nE Z    

x= п/6+пn; nEZ

Answer:

82

Step-by-step explanation:

You are looking for the hypotenuse.

c = ?

a = 80

b = 18

c^2 = a^2 + b^2

c^2 = 18^2 + 80^2

c^2 = 324 + 6400

c^2 = 6724

sqrt(c^2) = sqrt(6724)

c = 82 inches

Answer:

[tex]\boxed {\boxed {\sf 82 \ inches}}[/tex]

Step-by-step explanation:

We are asked to find the length of the rake.

We know it hits the wall 80 inches above the ground and the bottom of the rake is 18 inches away from the wall. The point where the top of the rake hits the wall and the distance away from the wall are the legs that form a right angle and the rake is the hypotenuse.

We want to find the hypotenuse or the length of the rake. We will use the Pythagorean Theorem.

[tex]a^2+b^2=c^2[/tex]

In this theorem, a and b are the legs and c is the hypotenuse.

The length of the legs are 80 inches (distance from ground to top of rake)  and 18 inches (distance from wall to bottom of rake). The hypotenuse is unknown.

Substitute the known values into the formula.

[tex](80 \ in)^2+(18 \ in)^2= c^2[/tex]

Solve the exponents.

[tex]6400 \ in^2+ 324 \ in^2= c^2[/tex]

Add.

[tex]6724 \ in^2=c^2[/tex]

We are solving for c, the hypotenuse, so we must isolate the variable. It is being squared. The inverse of a square is a square root, so we take the square root of both sides.

[tex]\sqrt {6724 \ in^2}= \sqrt{c^2}[/tex]

[tex]\sqrt{6724 \ in^2}=c[/tex]

[tex]82 \ in =c[/tex]

The length of the rake is 82 inches.

Answer:

19.365

Step-by-step explanation:

The Pythagoreum Theorum tells us that:

a² + b² = c²

where a and b are the legs and c is the hypotenuse.

BC is a leg; we'll lable it a.

AC is the hypotenuse thus labled c.

Plugging their lengths into the above formula will solve for the missing leg length.

5² + x² = 20²

25 + x² = 400

x² = 375

✓x = ✓3 x (5 x 5) x 5

x = 5✓15

x = 19.365

Answer:

wea did tha r come from??

Step-by-step explanation:

it is supposed to be d