Question

To solve the equation 7.5d=2.5d, Lin divides each side by 2.5d, and Elena subtracts 2.5d from each side. Will both moves lead to the solution? Explain your reasoning.

Answer 1

See Explanation

Explanation:

Given

`7.5d = 2.5d`

Analyzing Lin's

`(7.5d)/(2.5d) = (2.5d)/(2.5d)`

`3 = 1`

This isn't a solution because
`3 \\eq 1`

Analyzing Elena's

`7.5d - 2.5d= 2.5d-2.5d`

`5d = 0`

Divide through by 5

`d = 0`

Hence;

Going by the analysis above; only Elena's move will lead to a solution