Question

6x+7y=45 9x-7y=45 x=? y=?​

Answer 1

`6x+7y=45\\9x-7y=45`

Simply eliminate y to get the value of x (Because 7y-7y=0 which is easier to get the answer and faster)

`15x=90\\x=6`

15x=90 is from 6x+9x = 15x, 7y-7y = 0 and 45+45 = 90

We know the value of x, now for the value of y.

Substitute x = 6 into one of the equation, any equations but not all, just one.

So for me, I'll substitute x=6 in 6x+7y=45

`6(6)+7y=45\\36+7y=45\\7y=45-36\\7y=9\\y=(9)/(7)`

So the answer is x = 6 and y = 9/7