Which expressions are equivalent to (5⋅x)⋅3 ? 3⋅(5⋅x) 5⋅3+x⋅3 5⋅(x⋅3) 15x 5⋅3⋅x⋅3

Which shows the image of rectangle abcd after the rotation (x, y) → (–y, x)?

Write the pair of fractions as a pair of fractions with a common denominator

How many sides does a regular polygon have if each exterior angle measure is 45 degrees explain your answer, i really don't understand this.