Why did the world's first civilizations develop in river valleys?

Provided places to fish and hunt. Also, because when the lands flooded it then became fertile.

Explanation:

brought good soil for farming and was a good food resource

Explanation:

answer

explanation

the given equation is

we can rewrite this as:

let

then the equation becomes:

the factors of 8 that sum up to -9 are {-1,-8}

we split the middle term with these factors to obtain,

we factor by grouping to obtain:

apply the zero product property to get:

but

ayatollah khomeini can best be described as the leader who declared iran to be an islamic republic.