Question

Can someone please help me with this quick 8th grade math question?

Fiona and Iliana went to a going-out-of-business sale at a local video store. The store was advertizing all HD videos on sale for one price and all classic videos for a different price. Fiona bought 5 HD videos and 2 classic videos for $31. Iliana bought 5 classic videos and 3 HD videos for $30. Which system of equations can be used to find the prices of the classic and HD videos?

Answer 1

Hello

Answer 2

Hi

Answer 3

5h + 2c = $31
3h + 5c = $30
Choose an equation and solve for a variable
3h + 5c = 30
5c = 30 - 3h
c = (30-3h)/5
Substitute into another equation
5h + 2(30-3h)/5 = 31
5h + (60-6h)/5 = 31
5h + 12 - 6h/5 = 31
5h - 6h/5 = 19
3.8h = 19
h = 5
Resubstitute into original equation
5(5) + 2c = 31
25 + 2c = 31
2c = 6
c = 3

H = HD videos = $5.00 each
C = classic videos = $3.00 each

Answer 4

I don't get it @xGuardians ?

Answer 5

What don't you understand?

Answer 6

I mean the question is asking me for a system of equations.

Answer 7

Oh never mind

Answer 8

5h + 2c = $31
3h + 5c = $30
Is that all you needed?

Answer 9

Can you help with one more?

Thuy wrote the system of equations.

24x+36y=72
-16x+8y=80

If the second equation is multiplied by 3, what should the first equation be multiplied by to eliminate the x variable by addition?
@xGuardians

Answer 10

Yea lol

Answer 11

So all you really care about in this equation is the x values.
3(-16x) = -48x
24x * what value = 48x
So -48x and 48x cancel out.

Answer 12

So 0?

Answer 13

Nope.

Answer 14

24 * ? = 48

Answer 15

)=

Answer 16

2

Answer 17

Yeah. So the answer is two.

Answer 18

Sorry I'm just innately bad at math

Answer 19

I'll write it out. NP.

Answer 20

Which operations would create an equivalent system of equations with opposite like terms?
3x-3y=3
4x+5y=13
@xGuardians

Answer 21

=)

Answer 22

2(24x+36y=72)
3(-16x+8y=80)
BREAK
48x + 72y = 144
-48x + 24y = 240
______________________
0x + 96y = 384
So when you add them together you get 0x

Answer 23

Oh sorry I forgot to include the answer choices
A. The first equation can be multiplied by 5 and the second equation by 3.
B. The first equation can be multiplied by –4 and the second equation by –3.
C. The first equation can be multiplied by 4 and the second equation by –4.
D. The first equation can be multiplied by 3 and the second equation by 5.

Answer 24

?

Answer 25

A I think, when you apply it it will make the y-values cancel out.

Answer 26

Ok thanks so much that was the last one