Can someone me on this pls identify the property that is being applied at each step to simplify the expression

We are given

First expression:

We used property

power rule-II:

Product to power distribute  to each base

Second expression:

we used property

associative property of multiplication:

Third expression:

we used property

Product Rule:

Same base add exponents

Fourth expression:

we used property

Zero Exponent :

Anything to the zero power  (except 0) is one

Fifth expression:

we used property

Multiplicative identity:

Sixth expression:

We used simplification

y=-2.5x+12.5

step-by-step explanation:

5y=2x+10

y=0.4x+2

slope=-2.5

5=-2.5*3+b

b=12.5