anonymous
  • anonymous
what is the solution of x+y=7 2x-4y=8
Mathematics
  • Stacey Warren - Expert brainly.com
Hey! We 've verified this expert answer for you, click below to unlock the details :)
SOLVED
At vero eos et accusamus et iusto odio dignissimos ducimus qui blanditiis praesentium voluptatum deleniti atque corrupti quos dolores et quas molestias excepturi sint occaecati cupiditate non provident, similique sunt in culpa qui officia deserunt mollitia animi, id est laborum et dolorum fuga. Et harum quidem rerum facilis est et expedita distinctio. Nam libero tempore, cum soluta nobis est eligendi optio cumque nihil impedit quo minus id quod maxime placeat facere possimus, omnis voluptas assumenda est, omnis dolor repellendus. Itaque earum rerum hic tenetur a sapiente delectus, ut aut reiciendis voluptatibus maiores alias consequatur aut perferendis doloribus asperiores repellat.
jamiebookeater
  • jamiebookeater
I got my questions answered at brainly.com in under 10 minutes. Go to brainly.com now for free help!
jim_thompson5910
  • jim_thompson5910
we have a `y` in the first equation and a `-4y` in the second equation adding them up gives: `y+(-4y) = -3y` which isn't 0 like we want however we can change that `y` to `+4y` by multiplying by 4. Then notice how `4y + (-4y) = 0y = 0`
anonymous
  • anonymous
so it's 0?
jim_thompson5910
  • jim_thompson5910
to change the y to 4y, we have to multiply both sides of the first equation by 4 x+y=7 4*(x+y)=4*7 4x+4y = 28

Looking for something else?

Not the answer you are looking for? Search for more explanations.

More answers

jim_thompson5910
  • jim_thompson5910
This system x+y=7 2x-4y=8 turns into 4x+4y=28 2x-4y=8
jim_thompson5910
  • jim_thompson5910
Do you see how to solve 4x+4y=28 2x-4y=8 ??
anonymous
  • anonymous
i don't
anonymous
  • anonymous
would you subtract?
jim_thompson5910
  • jim_thompson5910
you add actually
jim_thompson5910
  • jim_thompson5910
add straight down 4x+4y=28 2x-4y=8 ----------- 6x+0y = 36 so 6x = 36 which means x = ???
anonymous
  • anonymous
6
jim_thompson5910
  • jim_thompson5910
yes
jim_thompson5910
  • jim_thompson5910
now take that x value and plug it into any equation that has x and y in it
jim_thompson5910
  • jim_thompson5910
then solve for y
anonymous
  • anonymous
12-47=8? am i doing that right?
anonymous
  • anonymous
i mean 12-4y=8
jim_thompson5910
  • jim_thompson5910
yes now solve for y
anonymous
  • anonymous
is y 0?
jim_thompson5910
  • jim_thompson5910
no
jim_thompson5910
  • jim_thompson5910
try again

Looking for something else?

Not the answer you are looking for? Search for more explanations.