Part of a $3,600 bonus was invested at 9% annual simple interest. The rest was invested at %8 annual simple interest. The total interest at the end of one year was $312. How much was invested in the %9 account?

  $2400

Step-by-step explanation:

Let x represent the amount invested at 9%. (3600-x) will be the amount invested at 8%. The total interest earned is then ...

  312 = 0.09x +0.08(3600 -x)

  24 = .01x . . . . subtract 288, simplify

  2400 = x . . . . divide by .01

$2400 was invested in the 9% account.

pentagon

step-by-step explanation:

the coordinates   a(5, -2), b(3,-1),c(-4,-4) d(-3,8) and e(-1,4) forms the vertices of the polygon when they are connected in order.

in order to classify that which polygon is it with the given coordinates, first count the number of vertices and then count the number of sides it can make with these vertices.

since, the given coordinates have five vertices, therefore, it will make five sides. moreover, pentagon is regular in nature therefore it will be convex.

now, a polygon with five sides is known as pentagon, therefore, the given polygon is the pentagon.

80

step-by-step explanation: