Is this relation a function?

Answer:

see explanation

Step-by-step explanation:

Using x and y to represent the 2 numbers with x > y , then

x + y = 15 → (1)

x - y = 11 → (2)

Adding the 2 equations term by term to eliminate y

2x = 26 ( divide both sides by 2 )

x = 13

Substitute x = 13 into (1)

13 + y = 15 ( subtract 13 from both sides )

y = 2

The 2 numbers are 13 and 2

arccos(2x) + arccos(x) = π/2

Apply cos to both sides, then expand the right side using the identity I mentioned in a comment:

cos(arccos(2x) + arccos(x)) = cos(π/2)

cos(arccos(2x)) cos(arccos(x)) - sin(arccos(2x)) sin(arccos(x)) = 0

Now think of arccos(2x) and arccos(x) as angles in two right triangles. Let θ = arccos(2x) and φ = arccos(x) (and let's also assume that both have measure between 0 and π/2). These are angles such that

cos(θ) = 2x

cos(φ) = x

In these triangles, you then have

sin(θ) = sin(arccos(2x)) = √(1 - 4x ²)

sin(φ) = sin(arccos(x)) = √(1 - x ²)

while

cos(θ) = cos(arccos(2x)) = 2x

cos(φ) = cos(arccos(x)) = x

So the original equation is transformed to

2x ² - √(1 - 4x ²) √(1 - x ²) = 0

Solve for x :

2x ² = √(1 - 4x ²) √(1 - x ²)

(2x ²)² = (√(1 - 4x ²) √(1 - x ²))²

4x ⁴ = (1 - 4x ²) (1 - x ²)

4x ⁴ = 1 - 5x ² + 4x ⁴

0 = 1 - 5x ²

x ² = 1/5

x = ± 1/√5

Now bearing in mind that we assume 0 < φ < π/2, we should have cos(φ) = x > 0, so we take the positive solution,

x = 1/√5

Answer:

Step-by-step explanation:

[tex]\displaystyle \Large \boldsymbol{} x^2+10x+9=0 \\\\ x^2+\underbrace{x+9x}_{10x}+9=0 \\\\x^2+x+\underline9x+\underline9=0 \\\\x(x+1)+9(x+1)=(x+9)(x+1)[/tex]

Given:

The ratio and rates:

1. 30 ft. To 60.Ft

2. 51 males to 21 females

3. 1,500 meters in 6 seconds

4. $36 for 4 rounds of shrimp

To find:

The fraction in simple terms for the given ratio and rates.

Solution:

1. 30 ft. To 60.Ft

[tex]\dfrac{30\text{ ft}}{60\text{ ft}}=\dfrac{1}{2}[/tex]

2. 51 males to 21 females

[tex]\dfrac{51}{21}=\dfrac{17}{7}[/tex]

3. 1,500 meters in 6 seconds

[tex]\dfrac{1500\text{ meters}}{6\text{ seconds}}=250\text{ meter/second}[/tex]

4. $36 for 4 rounds of shrimp

[tex]\dfrac{\$ 36}{4}=\$ 9\text{ per round of shrimp}[/tex]

Step-by-step explanation:

its on the picture.........

Answer:

x= 3 and x= -3

Step-by-step explanation:

x^2 -9 = 0

Factor x^2-9

(x+3)(x-3)

If x+3=0, then x= -3

If x-3=0, then x= 3

Answer:

200.96

Step-by-step explanation:

Volume of cone=(1/3)*pi*r^2*h

Volume=(1/3)*pi*16*12=64*3.14=200.96

Answer:

13.9

Step-by-step explanation:

For the 41° angle, x is the opposite leg, and 16 is the adjacent leg. The trig ratio that relates the opposite leg and the adjacent leg is the tangent.

tan A = opp/adj

tan 41° = x/16

x = 16 * tan 41°

x = 13.9085...

Answer: 13.9

it´s a polygon. letter c (decagon) should be right

hope it helps :)

Answer:

8 cm

Step-by-step explanation:

Answer:

4

Step-by-step explanation:

So first let's write the information we got

Angle BAC = 90 degrees

Midpoint of BC = M

AC = 6cm

Am= 5cm

Also I found MC = BM, since it has a line that represents both lines are same

so to find it we have to Pythagoras theorem (A^2 + B^2 = C^2), well it is question we have the 'A value and C Value', also we need to find the value of B to find the length of MC and BM

A = 5

C = 6

so therefore to find B^2, we have to do the reverse, we don't add but subtract

C^2 - A^2 = B^2

___________________________________________________________

Moving on to Calculation

6^2 - 5^2 = B^2

36 - 25 = B^2

B^2 = 9

B = √9

B = 3

MC and BM Length =  3 cm

____________________________

Now, we know the length we again need to use Pythagoras theorem to solve this.

Since we know

A = 5

B = 3

So..

A^2 + B^2 = C^2

5^2 + 3^2 = C^2

25 - 9 = C^2

C^2 = 16

C = √16

C = 4

Answer: You would use 7 cups of milk.

Step-by-step explanation:

Half of 14 is 7.

9514 1404 393

Answer:

  B.  even

Step-by-step explanation:

Functions are classed according to what happens when x is replaced by -x.

  f(-x) = f(x) . . . even

  f(-x) = -f(x) . . . odd

__

Here, we have ...

  f(-x) = 2/(-x)^2 = 2/x^2 = f(x) . . . . an even function

a school has 2500 pupils. when 52 boys and 1/9 of the girls are absent, the number of the boys present is equal to the number of girls. how many pupils does the school have ?

Let the number of boys be x

Data :

Total pupils = 2500

Absent no. of boys and girls = 52 and 1/9

Now,

Remaining no of pupils = 2500 - 52 ➝ 2448

Hence, the no. of girls absent = 1/9 of 2448 ➝ 272

Therefore,

Total no. of pupils absent = 52 + 272 ➝ 324

No. of pupils present = 2500 - 324 ➝ 2176

Henceforth, 2176 pupils are present

Answer:

sorry

Step-by-step explanation:

polynomial is not given

question is incomplete

Answer:

even i dont know can help

Answer:

B. Never

Step-by-step explanation:

When a number is irrational, it means that it cannot be written as a fraction.

I hope this helps!

pls ❤ and mark brainliest pls!

Answer:

c) when it is improper fraction

Answer:

y = 3/5×x + 1

Step-by-step explanation:

Slope intercept form y= mx + b

since slope = 3/5 => y= [tex]\frac{3}{5}[/tex]x + b

Plug point (-5,-2) to the equation -2 = [tex]\frac{3}{5}[/tex] x (-5) + b

=> b=1

Answer:

x = 35

Step-by-step explanation:

Let x be the one of the other angles

X is also the third angle since we know they are equal

The sum of the angles of a triangle is 180

110+x+x = 180

110 +2x= 180

2x = 180-110

2x= 70

Divide by 2

2x/2 = 70/2

x = 35

Answer:

[tex]x = 35 \degree[/tex]

Step-by-step explanation:

Let the unknown angle be x

Unknown Angles are equal to each other so,

[tex]x + x + 110 = 180[/tex]

sum of the interior angles in a triangle is 180°

[tex]2x + 110 = 180 \\ 2x = 180 - 110 \\ 2x = 70 \\ \frac{2x}{2} = \frac{70}{2} \\ x = 35 \degree[/tex]

Answer:

Option C, 93.6 mi³

Step-by-step explanation:

Volume of the triangular prism,

base area × height

= (8×3.9/2)×6

= 93.6 mi³

Answer:

3468 children.

Step-by-step explanation:

One apple per person.

The answer is C.) (0, 5)

Explaintion is in the pictures

I believe this is the answer if it isn't I'm sorry for wasting your time by answering.

Hope this helps!

Answer:

I am odd number my digits add up to 7 i am bigger than 50 and smaller 100

Answer:

2=124  124/2

4=248 248/4

5=310 310/5

8=496 496/8

Step-by-step explanation:

40 + 22 = 62

62 x 2 = 124

62 x 4 = 248

62 x 5 = 310

62 x 8 = 496

i think

1 hour = 60 minutes

3.5 hours x 60 = 210 minutes

210 minutes / 7.5 minutes per mile = 28 miles

Answer: 28 miles

Answer:

(2x+3y)^2

= (2x)^2 + 2(2x)(3y) + (3y)^2

= 4x^2 + 12xy + 9y^2

Answer:

4x^2 12xy +9y^2

Step-by-step explanation:

(2x+3y)^2

(2x+3y)(2x+3y)

FOIL

4x^2 + 6xy+6xy + 9y^2

4x^2 12xy +9y^2