Answer:
− 6 x + 3
Step-by-step explanation:
hope that helps :)
The minimum number of Halle will have 15 stacks.
x = 9
Sum of all angles of a triangle = 180
63 + 7x + 6x = 180
63 + 13x =180
13x = 180 - 63
13x = 117
x = 117/13