Question

Decide whether you would use the graphing, substitution, or elimination method to solve the following system of equations. Explain, in complete sentences, why you chose that method.
Part 2: Solve the following system of equations and show all of your work.

2x + 5y = −3
−15x − 5y = −10

Answer 1

Elimination method.

Answer 2

I would use elimination, because all the coefficients have no common factor bigger than 1, and the x coefficients are additive inverses. This will make it easier to use elimination.
2x+ 5y=-3
+-15x-5y=-10
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-13x =-13
using algebra: x=1.
2(1)+5y=-3
2+5y=-3
5y=-5
y=-1
(x,y) = (1,-1)