Question

Solve by elimination.
.3x + .4y = .8
.7x - .8y = -6.8
I know that x = -4 and y = -28, i just don't know how to get there. Help?

Answer 1

If you multiply the first equation by 2,
then subtract the two equations, that will cancel the 8y's

Answer 2

sorry not cancel, ELIMINATE, the 8y's

Answer 3

i know, i did all the steps but i got these weird equations and my friend said that it was wrong and since her answer seemed more logical i put it down.

Answer 4

cause now you have 1.3x = 6.8

Answer 5

are those 0.1 and 0.8??

Answer 6

.1?

Answer 7

sorry, 0.3... etc.. are they all decimals, make sure you put the 0.3 not just .3, very hard to see... anyways... my bad, you need to ADD the two equations because the 2nd eqn has a -0.8y

Answer 8

...huh

Answer 9

okay... i'll show you the math.

Answer 10

0.3x +0.4y = 0.8
0.7x-0.8y = -6.8

Right?

Answer 11

i got it

Answer 12

u got the answer?

Answer 13

yep