9514 1404 393
Answer:
1. yes
2. no
Explanation:
We can label the equations [1] and [2] to make the transformations to the equivalent system easier to describe.
1. The equivalent system is [1] +[2] and 2×[1]. Both of these are described as allowed transformations.
[1] +[2] is (-x +2y) +(-3x +9y) = (10) +(-15) ⇒ -4x +11y = -5
2×[1] is 2(-x +2y) = 2(10) ⇒ -2x +4y = 20
These resulting equations match the ones proposed for the equivalent system.
yes, the systems are equivalent
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2. The first equation of the proposed "equivalent" system is [1] +[2]. The second equation has no relation to the equations of the given system.
[1] +[2] = (-2x +3y) +(-11x -13y) = (14) +(-6) ⇒ -13x -10y = 8
no, the systems are not equivalent
(This is also shown in the attached graph. The original system is in red; the "equivalent" system is in green. Equivalent systems have the same solution. These do not.)