Question

A person has 20 coins, all nickels and dimes, worth $1.65. How many nickels are there?
7
8
13

Answer 1

If the man has x nickels, then he has 20 - x dimes.

Answer 2

ok

Answer 3

Nickels are 5 cents.
Dimes are 10 cents.
He has 165 cents.

\( \color{Black}{\Rightarrow x(5) + (20 - x)(10) = 165 }\)

Answer 4

ok so what do i solve first in this one

Answer 5

Well you must distribute the values, first of all.

Answer 6

Do you know how to distribute or afk?

Answer 7

ok so ya

Answer 8

kinda

Answer 9

\( \color{Black}{\Rightarrow x(5) = ....? }\)

Answer 10

5x

Answer 11

\( \color{Black}{\Rightarrow 10(20 - x) = ....? }\)

Answer 12

30-x

Answer 13

No, I'm not sure what you did here, but:

\( \color{Black}{\Rightarrow a(b \pm c) = (a \times b) \pm (a \times c) }\)

Answer 14

wouldnt it be 200-x

Answer 15

This means:

\( \color{Black}{\Rightarrow a(b + c) = (a \times b) + (a \times c) }\)

OR

\( \color{Black}{\Rightarrow a(b - c) = (a \times b) - (a \times c) }\)

Answer 16

200 is correct....but what about \(10 \times -x\)?

Answer 17

-10x

Answer 18

Correct. So back to the equation.

\( \color{Black}{\Rightarrow 5x + (200 - 10x) = 165 }\)

Answer 19

ok now get rid of the brackets

Answer 20

Yes.

Answer 21

-200 right

Answer 22

Well if there is a positive sign outside the brackets, then you just remove them like *SWOOSH*

Answer 23

If there is a negative sign, then you change the signs of the stuff in the bracket.

Answer 24

ok so then i just solve like *SWOOSH*

Answer 25

\( \color{Black}{\Rightarrow 5x + 200 - 10x = 165 }\)

I just *SWOOSH*ed them out ;)

Answer 26

combine like terms

Answer 27

Yes, what do you get?

Answer 28

-5x

Answer 29

\( \color{Black}{\Rightarrow -5x + 200 = 165 }\)

What do we do now?

Answer 30

-5x=-35

Answer 31

Yes, what do we do now?????????

Answer 32

x=-7

Answer 33

No....! you are very very close.

Answer 34

\( \color{Black}{\Rightarrow -a = -b \Longleftrightarrow a = b }\)

Answer 35

double b\negative right so 7

Answer 36

side note: if you think about it negative number of money doesnt make sense ;D

Answer 37

yes. 7.

Answer 38

ok thanks parth

Answer 39

Pleasure :D