-1x-4x = -17

-5x = -17

x= 17/5

etc

-3y is in both and will be easiest to

eliminate.

there are a few ways to do this

you can

-1x-3y=1

is also

-1x-3y-1=0

and

4x-3y=18

is also

4x-3y-18=0

since they both equal 0

they are equal to each other

-1x-3y-1=4x-3y-18

now we add 3y to each side

-1x-1=4x-18

subtract 4x from each side

-5x-1=-18

add 1 to each side

-5x=-17

divide each side by -5

x=17/5

now that we know what x is

we substitute that value back

into one of the original eqns

-1(17/5)-3y=1

is also

-17/5-3y=1

add 17/5 to each side

-3y=1+(17/5)

make LCD

-3y=(5/5)+(17/5)

add the fractions

-3y=22/5

now divide each side by -3

y=(-1/3)(22/5)=(-1*22)/(3*5)

y=-22/15