Adam and Devin both solve this system of equations:
y = -0.5x + 3
y = 1.5x + 0.2
Adam's solution is (1.4, 2.3). Devin's solution is (2.2, 1.7). They graph the equations to check their work.
Based on the graph, whose solution is more likely to be correct?
+773 I do not think we need a graph for this. We can just solve the system of equations to find out who is right.
y = -0.5x + 3
- y = 1.5x + 0.2
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0 = -2x + 2.8 --> 2x = 2.8 --> x = 1.4
Inserting x = 1.4 into the equation y = 1.5x + 0.2, we have y = 2.1 + 0.2 --> y = 2.3. The solution is (1.4, 2.3)
Adam's solution is correct.
- PM
+773 If you want to check Devin's solution, we can use the same equation of y = 1.5x + 0.2.
x = 2.2 and y = 1.7.
We have 1.7 = 1.5(2.2) + 0.2 --> 1.7 = 3.3 + 0.2 --> 1.7 = 3.5. This is not true, so Devin's solution is not correct. Adam's is correct.
