Photography interest group

Suppose there are x players in the eighth grade group and (x+5) players in the seventh grade group.

Then the equation is listed:

x(x+5)+(x+5)x=252，

Finishing: x 2 +5x- 126=0,

Solution: x 1 =- 14, x 2 = 9,

Where x=- 14 is irrelevant, (omitted)

A: There are 9 members in the eighth grade group.