How do you solve the system of equations #4x + y = - 26# and #- 7x - 3y = 53#?

1 Answer
Jan 17, 2018

(-5, -6)

Explanation:

We can solve for one and plug it into the other.

#4x+y = -26# is the same as #y = -4x - 26#

We can plug that into the second equation, getting

#-7x - 3 (-4x - 26) = 53#
#-7x + 12 x + 78 = 53 #

Combining similar terms,
#5x = -25 #
#x = -5 #

Plugging that back into the original equation,
#y = -4x - 26 #
#y = -4 (-5) - 26 #
#y = -6 #

So the answer is #(x,y) = (-5, -6)#. If you want to check, you can plug them into the original equations and find that they're correct.