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2 years ago

How to factor this expression: x^2-9?

Mathematics

1 answer:

Lena [83]2 years ago

7 0

Answer:

(x+3)(x-3)

Step-by-step explanation:

rewrite "9" as 3^2

so it is x^2-3^2

You use the difference of squares: a^2-b^2=(a+b)(a-b)

apply it: (x+3)(x-3)

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25 POINTS Trina's Toy Company charges $0.85 per pound to ship toys.

d1i1m1o1n [39]

Answer:

Part A

C = $.85p

For 2 pounds , the charge is $1.70

Part B

C = $.05 * p

Step-by-step explanation:

Part A

Cost = charge per pound * pounds

We know the charge per pound is $.85

C = $.85 * p

We want to ship 2 pounds

C = .85*2

C = 1.70

Part B

Cost = charge per pound * pounds

We know the charge per pound is now $.05

C = $.05 * p

3 0

2 years ago

Rent a truck charges a daily rental of 39$ plus 0.16$ per mile. a competing agency, ace truck rentals, charges 25$ a day plus 0.

charle [14.2K]

39 + 0.16m = 25 + 0.24m
39 - 25 = 0.24m - 0.16m
14 = 0.08m
14 / 0.08 = m
175 = m <=== they will cost the same at 175 miles

39 + 0.16(175) = 39 + 28 = $ 67
25 + 0.24(175) = 25 + 42 = $ 67
they will both cost $ 67 <=====

3 0

3 years ago

The diagram shows a right-angled triangle.

Alexus [3.1K]

Step-by-step explanation:

there is no diagram so I'm just going to guess this however

sin x = 6/9

sin x = 2/3

sin x = 0.67

x = sin inverse of 0.67

x = 42.1

8 0

2 years ago

Please math , help

Furkat [3]

Answer:

As both the mean and standard deviation are in the desired ranges, the tool passes the technical control.

Step-by-step explanation:

Mean of the batch:

The mean of the batch is the sum of all values divided by the number of items. So

$M = \frac{199+204+201+197+195+204+200}{7} = 200$

Mean in the desired interval.

Standard deviation:

Square root of the sum of the difference squared between each term and the mean, divided by the number of items. So

$S = \sqrt{\frac{(199-200)^2+(204-200)^2+(201-200)^2+(197-200)^2+(195-200)^2+(204-200)^2+(200-200)^2}{7}} = 1.18$

As both the mean and standard deviation are in the desired ranges, the tool passes the technical control.

7 0

2 years ago

What is the common difference between the terms in the following sequence?

Sergeeva-Olga [200]

Answer:

-6

Step-by-step explanation:

Take a couple of differences and see:

11 -17 = -6

5 -11 = -6

The common difference is -6.

8 0

3 years ago