x-5y=-15x−5y=−15x, minus, 5, y, equals, minus, 15 Complete the missing value in the solution to the equation.

Keiko has seven colors of lanyard. She uses three different colors to make a keychain. How many different combinations can she c

AleksAgata [21]

Combination = doesn't matter what order
Permutation = order matters

There are <u>two</u> methods to work out combinations.

Method 1 List out possibilities
123 124 125 126 127 134 135 136 137 145 146 147 156 157 167
234 235 236 237 245 246 247 256 257 267
345 346 347 356 357 367
456 457 467
567

For a total of 35 combinations.

Method 2 Use a formula.
It's a rather complicated one, so only use it if you have a lot of possibilities.

$\frac{n!}{r!(n-r)!} = \frac{7!}{3!(7-3)!} = \frac{7!}{3!*4!} = \frac{7*6*5*4*3*2*1}{3*2*1*4*3*2*1} = \frac{7*6*5}{3*2*1}=\frac{210}6=35$

(n is the number of choices, r is the amount you choose, and ! is a function that multiplies together all numbers down to 1)

7 0

4 years ago

Whole numbers are _____ integers. . . . .A. always. B. sometimes. C. never

guapka [62]

Whole numbers are sometimes integers.

$\boxed{ \ The \ Answer \ is \ B \ }$

<h3>Further explanation</h3>

The set of natural numbers (also called the set of counting numbers) is denoted by N: $\boxed{ \ N = \{1, 2, 3, ...\} \ }.$
Natural numbers together with zero called are called whole numbers. The set of whole numbers is denoted by W: $\boxed{ \ W = \{0, 1, 2, 3, ... \} \ }.$
The set of natural numbers are not enough for all the number problems in everyday life. For example, natural numbers cannot be used to write some winter temperatures, since such temperatures may be less than zero i.e., negative numbers.
The set of integers are the union of the set of negative numbers with the set of natural numbers and zero. The set of integers is denoted by Z: $\boxed{ \ Z = \{..., -3, -2, -1, 0, 1, 2, 3, ... \} \ }.$
The set of negative integers is denoted by Z⁻: $\boxed{ \ Z^- = \{ ..., -3, -2, -1 \} \ }.$
The set of positive integers is denoted by Z⁺: $\boxed{ \ Z^+ = \{1, 2, 3, ... \} \ }.$
The set of non-negative integers are the set of all positive integers together with zero.
The set of non-positive integers are the set of all negative integers together with zero.

Conclusion:

Whole numbers are sometimes integers because negative integers are not part of whole numbers. In other words, whole numbers are not fully integers.

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

Examples of integers around us:

The height of an airplane flight typically between 31,000 and 38,000 feet.
Ice melts at 0⁰C.
This diver is swimming at -20 m.

<h3>Learn more</h3>

9 ten thousand divided by 10 in unit form brainly.com/question/4786449
What represents the simplified form of an expression: 5(14 - 2)² ÷ 2 brainly.com/question/1602237
Explanations and an example of a question about the four types of number form brainly.com/question/4725342

Keywords: whole numbers are sometimes integers, always, never, natural, counting, zero, negative integers, positive, the set

7 0

4 years ago

Read 2 more answers

In its second year of operation, a local internet provider's profits were $171,500. If this amount was 666% of the company's fir

scoray [572]

The first year profit of the local internet provider was $ 22,389.04.

<h3>What was the profit of a company in its second year of operation?</h3>

According to the statement, we find that the profit of the company in its second year of operation is 666 % greater than its profit in its previous year, that is, the profit in its second year of operation is 7.66 times the profit in its first year of operation. Then, the missing profit is found by using the following arithmetic expression:

x = 171,500 / 7.66

x = 22,389.04

The first year profit of the local internet provider was $ 22,389.04.

To learn more on percentages: brainly.com/question/15308590

#SPJ1

5 0

2 years ago

C) How long is the potato in the air? *hint set h=0*<br> if h=-2(t-3)2+32

Galina-37 [17]

Answer:

if you meant to put $(t-3)^{2}$ , then the answer is 7

Step-by-step explanation:

h=-2 $(t-3)^{2}$ +32

solve for t

0=-2 $(t-3)^{2}$ +32

subtract 32 from both sides

-32=-2 $(t-3)^{2}$

divide both sides by -2

16= $(t-3)^{2}$

find suare root of 16

4= t-3

add 3 to both sides

7 = t

6 0

3 years ago

Is it possible to draw a triangle with angles 150°, 20° and 20°?<br> Explain your answer.

Maksim231197 [3]

Answer:

No, it is not possible.

Step-by-step explanation:

The Triangle Sum Theorem states that all the interior angles of a triangle will always add up to 180°, but 150 + 20 + 20 = 190.

7 0

2 years ago