Seventeen lines drawn in a plane, with no three concurrent and no two parallel, divide the plane into closed regions (bounded on all sides) and open regions. The number of closed regions is

120

Step-by-step explanation:

Make a chart:

Lines:                  0   1    2   3  4   5   6

Closed regions: 0   0   0   1   3   6   10

Find the number of numbers using the formula:

x 14 = x 14

                                  = 8.5 x 14

                                  = 119

119 + 1 = 120

(add 1 because we didn't count the first line in the formula)

I hope this helps :)

fd

step-by-step explanation: