Use elimination to solve the system. What is the value of y?:
3x+5y=16 and 8x-5y=28

Question

Use elimination to solve the system. What is the value of y?: 
3x+5y=16 and 8x-5y=28

phi · Answer

though indirect, I would add the 2 equations together.
can you do that ?

anonymous · Answer

Ohh add. Yup!

anonymous · Answer

I was subtracting.>~>

anonymous · Answer

y=4

phi · Answer

it is easy to add.  put a + sign in, like this
3x+5y=16 
8x-5y=28
3x+8x +5y + -5y = 16+28

that simplifies to 11x=44
x=4

note you want y , not x

anonymous · Answer

Okay. I tend to lock up with math. Thanks!:D

phi · Answer

what do you get for y ?

anonymous · Answer

4?

anonymous · Answer

Er sorry!

phi · Answer

I hope you notice x=4. y is not 4

jhannybean · Answer

hint: plug x=4 into any one of the two equations to solve for y.

anonymous · Answer

Ohmygod. Obviously. So sorry.._.

jhannybean · Answer

3(4) +5y = 16

5y = 16 - 3(4)

y = (16-3(4))/5

jhannybean · Answer

or plug x=4 into the other equation.

8(4) -5y = 28

-5y = 28 -(8(4))

y= [28-8(4)] / (-5)

anonymous · Answer

Okay got it. Thank you!c: