Question

Solve the system of equations by the addition method. If the system does not have a single ordered pair as a solution, state whether the system is inconsistent or dependent. -4x - 3y = 6 -20x - 15y = 30

A. No solution, inconsistent

B. (-24, -18)

C. (-18, -24)

D. Infinitely many solutions, dependent

Answer 1

@UnkleRhaukus

Answer 2

The addition method is also called the elimination method.
Lets begin...
-4x - 3y = 6 -->(-5)
-20x - 15y = 30
----------------
20x + 15y = -30 (result of multiplying by -5)
-20x - 15y = 30
---------------
0 = 0
we do not need to go any further.....when you get an answer at the end that is equal, like 2 - 2 or 13 = 13, all that means is that the equations have infinite solutions. Now if it would have come out like 2 = 3 or 5 = 5, then there would have been no solutions or infinite solutions.
Any questions ?

Answer 3

oops...that is supposed to be 2 = 2

Answer 4

oops...another typo....2 = 3 or 5 = -5, then there would have been no solutions or 0 solutions.
sorry my brain is just waking up....lol

Answer 5

mine keeps going back to sleep in the middle of class