Answer:
a) She did mistake in Step 2
b) when she take -3y common then the term should be: -3y(x+5) instead she wrote -3y(x-5)
Step-by-step explanation:
We need to find problem in Ms J solution.
Ms J solution:
[tex]Step \ 1: 4x^2 + 20x - 3xy - 15y\\Step \ 2: 4x(x + 5) - 3y(x - 5)\\Step \ 3: (x+5)(4x - 3y)[/tex]
She did mistake in Step 2 when she take -3y common then the term should be: -3y(x+5) instead she wrote -3y(x-5)
Correcting the mistake:
[tex]Step \ 1: 4x^2 + 20x - 3xy - 15y\\Step \ 2: 4x(x + 5)\mathbf{- 3y(x +5)}\\Step \ 3: (x+5)(4x - 3y)[/tex]