Factor and solve the quadratic equation <br><br> x^2 + 2x + 2 = 0

How many different twotwo-letter passwords can be formed from the letters

Anna [14]

Answer:

$70$

Step-by-step explanation:

GIVEN: two two-letter passwords can be formed from the letters A, B, C, D, E, F, G and H.

TO FIND: How many different two two-letter passwords can be formed if no repetition of letters is allowed.

SOLUTION:

Total number of different letters $=8$

for two two-letter passwords $4$ different are required.

Number of ways of selecting $4$ different letters from $8$ letters $=^8C_4$

$=\frac{8!}{4!4!}$

$=70$

Hence there are $70$ different two-letter passwords can be formed using $8$ letters.

5 0

3 years ago

You need to buy a 20-foot length of 15-wide carpet that costs $29.50 per square yard. How much will this cost?

Marianna [84]

The cost of the carpet will be $983.33

<h3>Calculating cost</h3>

From the question, we are to calculate how much the carpet will cost

From the given information,

The carpet has a length of 20 feet

and a width of 15 feet

First, we will covert the dimension to yard

NOTE: 1 foot = 1/3 yards

Thus,

20 feet = 20/3 yards

and

15 feet = 15/5 yards = 5 yards

Now, we will calculate the area of the carpet

Using the formula,

Area = Length × Width

Area of the carpet = 20/3 × 5 square yard

Area of the carpet = 33.33 square yard

Now, we have that

The carpet costs $29.50 per square yard

∴ The cost of the carpet = 20/3 × 5 × $29.50

The cost of the carpet = $ 983.33

Hence, the cost of the carpet will be $983.33

Learn more on Calculating cost here: brainly.com/question/24458165

#SPJ1

8 0

2 years ago

(PLEASE HELP)

Delvig [45]

The answer is 40

91+49=140
180-140=40

4 0

3 years ago

Read 2 more answers

For the function f(x) = x2 -12, find (f o f-1)(4) A. 0 B. 4 C. 10 D. 6

slega [8]

We actually don't need to do any computation. By definition, the inverse function $f^{-1}$ changes the role of input and output. So, if a function f maps x onto y, the inverse function maps y onto x.

You have to think like this: if the function makes a step further, the inverse function makes that same step back.

This means that the composition $f \circ f^{-1}$ is always the identity function $f(x) = x$ . In fact,

$(f\circ f^{-1})(x) = f(f^{-1}(x)) = x$

So, for every function, you have

$(f\circ f^{-1})(4) = f(f^{-1}(4)) = 4$

5 0

3 years ago

It costs $100 to rent the bowling alley, plus $4 per person. The cost for any number (n) of people can be found using the expres

d1i1m1o1n [39]

Answer:

It would cost $160 for 15 people to rent the bowling alley

Step-by-step explanation:

First, let's identify what we know:

1) It costs $100, just to rent the bowling alley.

2) We have to add $4 dollars, for every extra person.

3) The total cost can be found by using the expression 100 + 4n = x (n equals number of people, x equals total cost, 100 equals intial rent charge, and 4 equals the charge for each individual person)

So, just input 15 into the equation!

100 + 4(15) = x

100 + 60 = x

x = $160

7 0

3 years ago

Factor and solve the quadratic equation x^2 + 2x + 2 = 0