PLEASE HELP IM STUCK

Mathematics

1 answer:

Andreyy892 years ago

3 0

Answer:

Step-by-step explanation:

The question gives the first equation:

0.05N + 0.10D = 2.20

It can be rewritten as:

0.05$ times the number of nickels plus 0.10$ times the number of dimes is equivalent to $2.20.

Notice that 0.05$ or 5 cents is equivalent to one nickel and 0.10$ or 10 cents is equivalent to one dime.

The question asks for N+D. We know that N stands for the number of nickels Daniel has and D stands for the number of dimes Daniel has. We also know that Daniel only has dimes and nickels in his pocket. Therefore N+D most be equivalent to the total number of coins, which is given in the question to be equal to 23 coins.

Therefore...

N+D = 23

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Now assume $n=2\ell$ is even. Then $n^2=4\ell^2$ . If $\ell=2j$ is even, then you will always be able to write

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So you conclude that

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