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3 years ago

For what values of a are v = a i − j + k and w = a i + a j − 3 k perpendicular? give exact values.

1 answer:

3 0

The vectors are perpendicular when their dot product is zero. That is
.. a^2 -a -3 = 0
.. (a -1/2)^2 -13/4 = 0
.. a = (1 ±√13)/2

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A couple lives in Florida for 1/3 of the year. Each year has 12 months. What fraction of a year, in twelfths, does the couple no

zhenek [66]

Answer:

4/12

Step-by-step explanation:

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7 0

3 years ago

1. A submarine is 40 meters below sea level. It goes up 12 meters, then goes down 30 meters. What is the submarine's new positio

Lilit [14]

Answer:

Question Number 1: C. -58 meters

Question Number 2: 1.45 lbs

Step-by-step explanation:

Question Number 1:

40 - 12 = 28 meters below sea level

28 + 30 = 58 meters below sea level . So respectively its negative, so -58 would be your answer .

Question Number 2:

To figure out how many pounds of carrots are in each cake, divided 7.25 by 5. That equals 1.45. So one cake needs 1.45 pounds of carrots.

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2 years ago

Please answer quickly Thank You

Nina [5.8K]

Answer:

A. $ 46

B. 12 people.

Step-by-step explanation:

From the question given above, we obtained the following:

C(x) = 6.5x + 20

Where:

C => total cost of bowling

x => number of people

A. Determination of the of bowling for 4 people.

Number of people (x) = 4

Total cost (C) of bowling =?

C(x) = 6.5x + 20

C(4) = 6.5(4) + 20

C(4) = 26 + 20

C(4) = $ 46

Thus, it will cost $ 46 for 4 people to bowl

B. Determination of the number of people that can bowl for $ 98.

Total cost (C) of bowling = $ 98

Number of people (x) =?

C(x) = 6.5x + 20

98 = 6.5x + 20

Collect like terms

98 – 20 = 6.5x

78 = 6.5x

Divide both side by 6.5

x = 78 / 6.5

x = 12

Thus, 12 people can bowl for $ 98.

3 0

2 years ago

PLLKEEASE HELPPPPPPP ASAPP

erica [24]

Answer:

x = 19

Step-by-step explanation:

(5x + 4)° + (x - 2)° + (3x + 7)° = 180°

(5x + x + 3x)° + (4 - 2 + 7)° = 180°

9x° + 9° = 180° → ÷9

x + 1 = 20

x = 20 - 1

x = 19

7 0

2 years ago

How much money will you have if you started with $45 and put it in an account that earned 10% every year for 20 years

Veronika [31]

Probably it's all wrong
4.5 = 10 %If is the same then 4.5*20+45=135
If not then
FV=P(1+r)n45* (1+0.1)20 = 45*6.727=302.737

6 0

2 years ago