Find an explicit formula for the arithmetic sequence 12
,
5
,
−
2
,
−
9
,
.
.
.
12,5,−2,−9,...12, comma, 5, comma, minus, 2, comma, minus, 9, comma, point, point, point.
Note: the first term should be
a(1)
a(1)start text, a, left parenthesis, 1, right parenthesis, end text.

Someone answer this asap for the length, in feet, of a rectangular rug is represented by the expression 5x² + 2x. the width, in feet, is represented by the expression 3x². which expression represents the perimeter, in feet, of the rug? a. 8x² + 2x b. 8x² + 4x c. 16x² + 2x d. 16x² + 4x