x^8:x^4=x^(8-4)=x^4
(2c)^15 * (2c)^5=(2c)^(15+5)=(2c)^20
x^7 = x^7 : x^9=x^(7-9)=x^(-2)x^9
27c^5=1.5c^(5-6)=1.5c^(-1)18c^6
x^8:x^4=x^(8-4)=x^4
(2c)^15 * (2c)^5=(2c)^(15+5)=(2c)^20
x^7
= x^7 : x^9=x^(7-9)=x^(-2)
x^9
27c^5
=1.5c^(5-6)=1.5c^(-1)
18c^6