How do solve the following linear system?: -6x+5y=1 , 7x+2y=2 6x+5y=1,7x+2y=2?

1 Answer
Feb 21, 2018

By substitution.
x = 8/47x=847, y = 19/47y=1947

Explanation:

-6x+5y = 16x+5y=1
+7x+2y = 2+7x+2y=2

We can take out x of the first equation, for example ;

x = (5y-1)/6x=5y16

and we substitute it into the second equation and make all denominators equal :

7((5y-1)/6) + 2y =27(5y16)+2y=2

(35y-7)/6 + (12y)/6 = 12/635y76+12y6=126

Multiply both sides by 66.

35y-7 + 12 y = 1235y7+12y=12

47y = 1947y=19

y = 19/47y=1947

Then we take this value and put it into our equation for xx.

x=((95/47) - 1)/6x=(9547)16

x=(48/47)/6 = cancel(48)/47 * 1/cancel(6) = 8/47