How do you solve the system of equations x+3y=-7x+3y=7 and -x-3y=1x3y=1?

1 Answer
Apr 25, 2017

No No solutionsolution

Explanation:

1. x + 3y = -71.x+3y=7
2.-x-3y = 12.x3y=1

Consider 1.1.
x = -7 - 3yx=73y

Substitute the value of x from 1.1. to 2.2.:
-(-7-3y) -3y = 1(73y)3y=1
7 + 3y - 3y = 17+3y3y=1
7 = 17=1

This means that there is no solution to the system, thus these lines must be parallel. If you convert both 1.1. and 2.2. to the form y = mx + by=mx+b, you will see the mm values, or the slope of both lines is the same, thus they will never intersect, hence no solution.