Question

A metal worker has several 1-kilogram bars of a metal alloy that contain 23% copper and several 1-kilogram bars that contain 79% copper. How many bars of each type of alloy should be melted and combined to create 48 kilograms of a 44% copper alloy? Set up and solve a system of equations to find the answer.

Answer 1

What method of system of equations is this?

Answer 2

@dhirensharma would you mind helping me out?

Answer 3

yup bring it on!!

Answer 4

okay soo i will give you the equations in a sec

Answer 5

btw do you want the solutions or the method that u wanna use ??

Answer 6

@dhirensharma i want the method and then i'll do it and you'll see if i did it right?

Answer 7

all right so you can do it by subtitution or elimination method but since this involves decimals you can do it by whatever way u find easier out of these 2 methods

Answer 8

@dhirensharma oh okay i'll do substitution do you know the equation?

Answer 9

yup i will have them here fr ya in a sec

Answer 10

x+y=48
.23x+.79y=12.32

Answer 11

remember when you are given percents you gotta convert them into decimals by dividing them with 100

Answer 12

@dhirensharma thank you!! i'll come back to you when i get the answers

Answer 13

yup i will be waiting

Answer 14

x+y=48
0.23x+0.79y=12.32
0.23(48-y)+0.79y=12.32
11.04-48y+0.79y=12.32
-48y+0.79y=12.32-11.04
-47.21=1.28
x+-47.21=48
x=95.21

Answer 15

@briana.img wait sorry i gave u the wrong equation here are the right ones
x+y=48
.23x+.79y=21.12

Answer 16

sorryyyyyyy

Answer 17

@dhirensharma omg ok but thanks!!

Answer 18

i am sorry but up i m sure these are absolutely right

Answer 19

i think i did something wrong but you'll see when i send in the final thing

Answer 20

okay

Answer 21

x+y=48
0.23+0.79=21.12
0.23(48-y)+0.79y=21.12
11.04-48y+0.79y=21.12
-48y+0.78y=21.12-11.04
-47.21=10.08

Answer 22

do i use 10.08 or -47.21 in x+y=48 ?!!?

Answer 23

okay so i got y=18

Answer 24

know ur mistake in a sec

Answer 25

21-6y+5.05y=24.10
11.04-48y+0.79y=21.12
u made the same mistake u made earlier
multiplication error

Answer 26

@dhirensharma where did "21-6y+5.05y=24.10" come from?

Answer 27

disregard it thats not part of question i sent it accidentally

Answer 28

so when u were multiplieng by using distributive property u made an error

Answer 29

do u know your error??

Answer 30

@dhirensharma not really :(

Answer 31

okay so i will send you the equations where u made the errror

Answer 32

ok

Answer 33

0.23(48-y)+0.79y=21.12
11.04-48y+0.79y=21.12

Answer 34

let me know if u get it now

Answer 35

so what was i suppose to do?

Answer 36

0.23(48-y)+0.79y=21.12
11.04-.23y+.79y=21.12

Answer 37

@dhirensharma ooooh okay

Answer 38

0.23y*-y=-0.23y

Answer 39

yup

Answer 40

like i said you are pretty good with the concept but be careful while multiplying ;)

Answer 41

i'm stuck on this -0.23y+0.79y=21.12-11.04

Answer 42

added -0.23 and 0.79 and got 0.56

Answer 43

thats right don't frget the y though

Answer 44

that's right?!?!
how?!!?

Answer 45

thought you said it was 18

Answer 46

-0.23y+0.79y=.56y

Answer 47

i meant don't frgt the y at the end of .56

Answer 48

.56y=10.08?!

Answer 49

OOOH OKAY

Answer 50

i learned this method from an example so i guess i didn't fully grasp it

Answer 51

incase u need more help i can send u a video explaining this stuff

Answer 52

how about i send it tommorow cause i am in the middle of a summer school so my hands are full today

Answer 53

@dhirensharma i'm in the middle of summer school too thanks for helping me out!! hopefully i can survive on the next problems!! good luck

Answer 54

heheeh allright so what school are u in??

Answer 55

i m in chaparral high

Answer 56

@dhirensharma oh so you're in vegas?!!?

Answer 57

nope close to vegas though

Answer 58

scottsdale AZ

Answer 59

@dhirensharma i got to ECTA

Answer 60

@dhirensharma oh there's a school here with the same name

Answer 61

go*

Answer 62

thats surprising
so are u frm arizona ??

Answer 63

@dhirensharma no nev ada

Answer 64

coool place here in AZ it's hot as helllll

Answer 65

@dhirensharma yeah i just visited arizona i went to the grand canyon lmao

Answer 66

awesome place isn't it but i bet u got tanned!!?!!?!!

Answer 67

@dhirensharma just a bit not much :p

Answer 68

allright so is there any other question u need help with??

Answer 69

@dhirensharma yeah i just @'d you in this new question