Please help me with this question! Thank You!!
Solve the system:
(8/5)x + (1/5)y = -9/5
8x + y = -9

Question

Please help me with this question! Thank You!!
Solve the system:
 (8/5)x + (1/5)y = -9/5
  8x + y = -9

anonymous · Answer

@zepdrix

zepdrix · Answer

So you'll notice in the first equation, every TERM is being divided by 5, see the 1/5? Just look closely! :3

So we can simplify that equation a little bit, if we multiply both sides by 5.

anonymous · Answer

then the both equation will be the same! same line too!

zepdrix · Answer

Oh my! :O true story!

zepdrix · Answer

@hartnn FIX ITTTT, i always forget this stuff :D lol

hartnn · Answer

yeah, its same.....now subtract both the equations , what u get ?

anonymous · Answer

0=0
all real numbers?

anonymous · Answer

what I dont understan is how my teacher got (a, -9-8a) (dependent)

hartnn · Answer

thats is correct. 
since you get 0=0 which is an identity, the solution is infinite numbers.

hartnn · Answer

yeah, so u take one variable as t

hartnn · Answer

and find other variable in terms of t

hartnn · Answer

'a' here.

hartnn · Answer

let x=a, find y

anonymous · Answer

ok....is it the same as "all real numbers"

hartnn · Answer

yup.

hartnn · Answer

but since one variable can be expressed as other, we usually write solution in terms of one independent variable only.

anonymous · Answer

so is it just another way of expressing the answer?

hartnn · Answer

u can say more accurate way ...

anonymous · Answer

oh ok! thank you, got it! :)

hartnn · Answer

zep, u got it too ?
welcome ^_^

hartnn · Answer

lets move to next question...