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3 years ago

Prove (correctly) that if 1 = -1, then 2=1

Mathematics

1 answer:

Nitella [24]3 years ago

6 0

Answer:

This may not be entirely satisfied proof but you should get the idea.

Proof: Start with 1 = -1.

Then we know that if a= b then a + c = b + c and also a / c = b / c.

So we can add 1 to both sides.

We have 1 + 1 = -1 + 1 ⇒ 2 = 0.

Now divide both sides by 2 and we would have 1 = 0.

Now add both sides by 1. This yields 2 = 1.

Therefore if 1 = -1 then 2 = 1.

QED

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A test requires that you answer either part A or part B. Part A consists of 7 true-false questions, and part B consists of 5 mul

jeka94

Answer: 3253

Step-by-step explanation:

Given : A test requires that you answer either part A or part B.

Part A consists of 7 true-false questions.

i.e. there are 2 choices to answer each question.

Now, the number of ways to answer Part A : $2^7=128$ (1)

Part B consists of 5 multiple-choice questions with one correct answer out of five.

i.e. there are 5 choices to answer each question.

Now, the number of ways to answer Part B : $5^5=3125$ (2)

Now, the number of different ways to completed answer sheets are possible= $128+3125=3253$ [Add (1) and (2) ]

5 0

4 years ago

During a spring clearance sale, Sears advertise 1/4 off the list of Model II microwave ovens and an additional 1/5 off the sale

ozzi

Answer:

$ 75.

Step-by-step explanation:

From the information above,

List price of model II = $240

Sale price of the clearance sale is 1/4 off the list price of Model II microwave oven and additional 1/5 of the sale price for oven that are scratched and dented.

Therefore,

Let the sale price be X,

= (1/4)*(list price) + (1/5)*X

X = (1/4)*(240) + (1/5)*X

X = 60 + (1/5)X

Solving for X,

X - (1/5)X = 60

(4/5)X = 60

X = (60*5)/4

= $75.

4 0

3 years ago

Given that x:y=5:1 find 4x+5y:3x

kotykmax [81]

Answer:

5:3

Step-by-step explanation:

When the ratio says x:y=5:1, it means that x is 5 times greater than y. So, plug in 5 for x and 1 for y.

4(5)+5(1):3(5)

20+5:15

25:15 , if simplified then the ratio 5:3

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3 years ago

The manager of a plant nursery bought 120 lb of soil to use for potting plants. The manager can put 5 lb into each of the small

zepelin [54]

Answer:

The intercept are the number of each of the pots used when no soil was put in the other pot.

When no soil was put in the large pots, then 120/5 = 24 small pots will be filled.

When no soil was put in the small pots, then 120/12 = 10 large pots will be filled.

Therefore, the points Labelled are (24, 0) and (0, 10)

Step-by-step explanation:

Please mark me as the BRAINLIEST please.

3 0

3 years ago

Read 2 more answers

Is substitutions the best method to use when one variable is already known

8_murik_8 [283]

There’s two ways to substitute, but i think you mean if you know x but don’t know y. if that is true, then yes use substitution

8 0

2 years ago

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