Answer
Only Lin's moves will lead to the solution.
Explanation
To find d, you need to have variables on one side, and constants on the other. Elena is wrong because her move cannot be done to find the solution.
I'll explain using examples and solve the problem step by step.
First let's start with Lin's solution... dividing by 2.5d.
Divide 2.5d from both sides.
7.5d divided by 2.5d is 3.
2.5d divided by 2.5d is 1.
3=1
This actually means unidentified because 3 does not equal 1.
Now let's see if Elena's solution.
Subtract 2.5d from both sides.
7.5d minus 2.5d equals 5d.
2.5d minus 2.5d equals 0.
5d=0.
d=0.
The actual answer is unidentified because 7.5d can never equal 2.5d.
I'll prove it to you.
If d is 1, then you'll get 7.5=2.5, which is not right.
So only Lin's solution is correct.
(In your explanation don't use the word "we" or "they" or "I" and I'm doing this so you can actually do work instead of asking Brainly and copy and pasting ☺)
