Surds simultaneous equations.

I can rearrange $5x-3y=41$ into x= and y=. but when I try and substitute them into the other equation I can't get anywhere at all. I've tried making x or y the subject of the second equation but again once I've done that I can't get anywhere.

5x- 3y = 41 Rearrange to get x = (41 + 3y)/5
Sbstitute into second equation = (7 root2 x)(41 + 3y over 5) + 4root2y = 82
Then I try getting rid of the fraction bymultiplying each side with 5, but can't get any further.

Then do you multiply them by root 2?

Thanks. Got there in the end. Y=5√2 - 7 and substitute to get X.

Just need a bit of help here guys. Im doing fine in all my modules (Im doing full further maths), but theres one question in my book that I can't do for some reason. I can do all of the questions before and after it, but this one just won't work.

Solve the simultaneous equations

$5x-3y=41$
$(7\sqrt2)x+(4\sqrt2)y=82$

I have tried finding x and y from the first equation and subbing in, and also expanding the second brackets then multiplying by sqrt2 for some reason.

Any help?

Thanks, I've already worked it out though. It took me long enough.

Once you get to the step you mentioned you can multiply up to

$35x-21y=287$
$35x+20y=205\sqrt2$

Then subtract to get

$-41y=287-205\sqrt2$

Then divide by 41

$-y=7-5\sqrt2$

Rearranging to

$y=5\sqrt2-7$


Then I just subbed in my result.

Thanks for all the help guys.

How did you get the 205?