Answer:
Substitution property of equality
Explanation:
Given
and

Then

Required
State the property
From the list of options, (d) answers the question.
This is so because:
Substitution property of equality states that
If
then

In other words, both can replace one another.
So if
, then 2y + 1 can be substituted for x in
So:
becomes

Hence, it is substitution property of equality