Find the value of x
6.1 - angles of polygons

There are 23 sharks and 7 octopi in the aquarium

If the total number of animals in the tank is 30, therefore;

If the total number of legs in the tank is 171 with starfish having 5 legs and Octopus having 8 legs, the required expression will be:

From equation 1, x = 30 - y ................... 3

Substitute equation 3 into 2 to have:

5(30-y) + 8y = 171

150 - 5y + 8y = 171

3y = 171 - 150

3y = 21

y = 7

Recall that x = 30 - y

x = 30 - 7

x = 23

Hence there are 23 sharks and 7 octopi in the aquarium

Learn more on simultaneous equation here: https://brainly.com/question/148035

Answer:

B,D,E

Step-by-step explanation:

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

[tex]2x + 2y = \sqrt{180} \\ = > 2x + 2( \frac{x}{2} ) = \sqrt{180} \\ = > 2x + x = \sqrt{2 \times 2 \times 3 \times 3 \times 5} \\ = > 3x = 2 \times 3\sqrt{5} \\ = > 3x = 6 \sqrt{5} \\ = > x = \frac{6 \sqrt{5} }{3} \\ = > x = 2 \sqrt{5} [/tex]

[tex]x.y \\ = x \times \frac{x}{2} \\ = \frac{ {x}^{2} }{2} \\ = \frac{ {(2 \sqrt{5} )}^{2} }{2} \\ = \frac{4 \times 5}{2} \\ = \frac{20}{2} \\ = 10[/tex]

Answer:

10

Hope you could get an idea from here.

Doubt clarification - use comment section.

Answer:

b

Step-by-step explanation:

Given

2x + 2y = [tex]\sqrt{180}[/tex] = [tex]\sqrt{36(5)}[/tex] = 6[tex]\sqrt{5}[/tex]

and y = [tex]\frac{x}{2}[/tex] , then

2x + (2 × [tex]\frac{x}{2}[/tex] ) = 6[tex]\sqrt{5}[/tex]

2x + x = 6[tex]\sqrt{5}[/tex]

3x = 6[tex]\sqrt{5}[/tex] ( divide both sides by 3 )

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

and y = [tex]\frac{2\sqrt{5} }{2}[/tex] = [tex]\sqrt{5}[/tex]

Then

xy = 2[tex]\sqrt{5}[/tex] × [tex]\sqrt{5}[/tex] = 2 × 5 = 10 → b

Answer:

Scale factor = Dimensions of the new shape ÷ Dimensions of the original shape.

Answer: SAS

Because there is a mark showing that one pair of sides are congruent, the stars showing that one pair of angles are congruent, then the triangles are sharing a line (which means that they are congruent)

Step-by-step explanation:

(5a³-2)(5a³+2)

Answer:

150% of 45 less than 100, greater than 100 but less than 150. Or greater than 150?

Answer:

Less than 100?                                                  YES

Step-by-step explanation:

150% of 45 less than 100, greater than 100 but less than 150, or greater than 150?

"150% of 45 "

150% (45)

1.5*(45) = 67.5      

Less than 100?                                                  YES

Greater than 100 but less than 150               NO

Greater than 150?                                             NO

Answer:

y = - 1

Step-by-step explanation:

Note the y- coordinates of both points are equal, both - 1

This indicates the line is horizontal and parallel to the x- axis with equation

y = c

where c is the value of the y- coordinates the line passes through

The line passes through (7, - 1 ) and (- 3, - 1 ) with y- coordinates - 1 , then

y = - 1 ← equation of line

Answer:

-5/6

Step-by-step explanation:

to find the slope between to lines we can subtract the second y by the first y and subtract the second x by the first x and dividing them by each other

(18 - 3) / (-21 + 3)

minusing a negative is basically adding

after subtracting them you get this

15 / -18

then reduce

-5/6

the slope is -5/6

Answer: Situation:

Step-by-step explanation:

You are walking in a grocery store and you see a nice deal saying that if you buy 4 batches of 2 bananas, you will get 5 extra bananas free of charge. However you see in another store that for the same price, you can buy 12 batches of 2 bananas but 11 of them are always bad and are needed to be thrown out. You calculate which deal is better and you decide on the first one because you hate stinking bananas. Hope this helps!

:)

Answer:

f is equivalent to 15 and when you replace x with -5 you will have to multiply 15×(-5) and you will get -75 as an overall answer.

Answer:

n = [tex]\frac{1}{3}[/tex] , n = [tex]\frac{1}{2}[/tex]

Step-by-step explanation:

6n² - 5n - 7 = - 8 ( add 8 to both sides )

6n² - 5n + 1 = 0 ← in standard form

Consider the product of the factors of the coefficient of the n² term and the constant term which sum to give the coefficient of the n- term

product = 6 × 1 = 6 and sum = - 5

The factors are - 3 and - 2

Use these factors to split the n- term

6n² - 3n - 2n + 1 = 0 ( factor the first/second and third/fourth terms )

3n(2n - 1) - 1(2n - 1) = 0 ← factor out (2n - 1) from each term

(2n - 1)(3n - 1) = 0 ← in factored form

Equate each factor to zero and solve for n

3n - 1 = 0 ⇒ 3n = 1 ⇒ n = [tex]\frac{1}{3}[/tex]

2n - 1 = 0 ⇒ 2n = 1 ⇒ n = [tex]\frac{1}{2}[/tex]

Answer:

Solution given:

weight of moon=1/6 th of Earth

If weight of Earth is 18/5 kg

weight of moon=?

we have

weight of moon: 1/6 of weight of Earth

=1/6*18/5

=3/5kg

Its weight on moon is 3/5 kg

Answer:

1

Step-by-step explanation:

if you use a calculator, it will come up as 1. I don't know why, but it does.

Hope this helps!

10.

In order to find the missing value, we need to divide 173.1, by 17.31:

173.1 / 17.31 = 10

Dividing the product (173.1) by one value in the equation (17.31) can represent what the missing value is, in order for 17.31 to equal 173.1

17.31 · 10 = 173.1

173.1 / 10 = 17.31

Based on the tip left and its proportion of the total bill, the following answers are true:

A tip of $2.60 was left and this is said to be 20% of the bill including the tax.

The total bill is therefore:

Tip = Total bill x 20%

2.60 = Total bill x 20%

Total bill = 2.60 / 20%

= $13.00

We can see that the tax rate was not needed to compute the total bill.

In conclusion, the tax rate was irrelevant and the total bill was $13.00.

Find out more about taxes and tips in bills at https://brainly.com/question/24976122.

Answer:

The answer should be 72.

Step-by-step explanation:

You're finding the interest earned. I = Prt, I for simple interest, P for principal, r for rate, and t for time.

Substitute p for $800, r for 9%, and t for is 1 year.

You would multiply these three numbers together.

$800(0.09)(1) should give you 72.

Answer:

A

Step-by-step explanation:

Correct option is A)

Let a 3-digit number ABC

Case (1)

If A=7, then B  and  C can be any digit but not 7

so, total 9 digits (0,1,2,3,4,5,6,8,9) can replace B and C

Then total such combinations =1(9)(9)=81

Case (2)

If B=7  then A can be any digit but not  0 and 7, because if A=0 it will be a 2-digit number.

And C can be any digit but not 7

Then total combinations =(8)(1)(9)=72

Case (3)

If C=7  then A can be any digit but not 0 and 7, because if A=0 it will be a 2-digit number.

And B can be any digit but not 7

Then total combinations =(8)(9)(1)=72

So, total numbers between 99 and 1000 which have exactly one of their digits as 7 are =81+72+72=225

Answer:

2 stops, 30 min

Step-by-step explanation:

to figure this out we have to divide B's time by A's time. 30÷15 is 2.

Answer:

blue

Step-by-step explanation:

a b c d e

1 2 3 4 5

27-25=2

so b, or blue

Answer:

the answer is X=12 Y=4

Step-by-step explanation:

X is 3 times the amount of Y and also 8 more. 4x3=12 and 12 is 8 bigger than 4

Answer:

b

Step-by-step explanation:

-8 Is the slope and yintecept is 0,1

Answer:

32

Step-by-step explanation:

area=2(lb+bh+lh)

2(3×2+3×2+2×2)

2(6+6+4)

2(16)

=32

Answer:

01)05

02)45°

03)120°

04)60°

Step-by-step explanation:

Have a great day!