Answer: Plug in x=6 and x=2. If you get the same answers for x=6 and x=2, we know that the equations are equal.
Explanation:
To determine if the two equations are equivalent, we can plug in x=6 and x=2 to both equations and see if you get the same result.
2x+4-1 [plug in x=6]
2(6)+4-1 [multiply]
12+4-1 [add and subtract]
15
For x=6, we get 15 for 2x + 4-1.
3+x+x [plug in x=6]
3+6+6 [add]
15
Since we plugged in x=6 for both equations and got 15 for both answers, we know that the two equations are equivalent.
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Let's plug in x=2 to make sure we are correct.
2x+4-1 [plug in x=2]
2(2)+4-1 [multiply]
4+4-1 [add and subtract]
7
For x=2, we get 7 for 2x + 4-1.
3+x+x [plug in x=2]
3+2+2 [add]
7
Since we plugged in x=2 for both equations and got 7 for both answers, we know that the two equations are equivalent.
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With the confirmation of plugging in both x=6 and x=2, and getting the same answers, we know that the two equations are equivalent.