How do you solve the system of equations #-8x + 3y = 7# and #13x - 3y = - 17#?

1 Answer
Apr 28, 2017

Answer:

See explanation.

Explanation:

The starting system can be written as:

#{(-8x+3y=7),(13x-3y=-17) :}#

We can see that the coefficients of #y# are opposite numbers, so if we add both sides of the equations we get rid of one variable:

#5x=-10 => x=-2#

Now if we substitute the calculated value of #x# to any of the equations we can calculate the remaining variable #y#:

#-8*(-2)+3y=7#

#16-3y=7#

#-3y=-9 => y=-3#

Finally we can write that the solution is:

#{(x=-2),(y=-3) :}#