Is (5, -1) a solution to this system of equations: #3x+6y = 9# and #-2x-y = -6# ?

1 Answer
Jan 19, 2017

Answer:

No. See below, the second equation is not solve therefore this point is not a solution for this set of equations.

Explanation:

To determine if this point is a solution to the system of equations we need to substitute the point into each equation and see if it solves the equation.

We will substitute #color(red)(5)# for #color(red)(x)# and #color(blue)(-1)# for #color(blue)(y)#

Then #3color(red)(x) + 6color(blue)(y) = 9# becomes:

#(3 xx color(red)(5)) + (6 xx color(blue)(-1)) = 9#

#15 - 6 = 9#

#9 = 9#

And #-2color(red)(x) - color(blue)(y) = -6# becomes:

#(-2 xx color(red)(5)) - (color(blue)(-1)) = -6#

#-10 + = -6#

#-9 != -6#

Because the second equation is not solve this point is not a solution for this set of equations.