Answer:
8x-4
Step-by-step explanation:
(3x-5)+(5x+1)
=3x-5+5x+1
=8x-4
D. Positively skewed
There are 19 big marbles
10a + 3b = 209
a = 3b
3b = 3b
10a + a = 209
11a = 209
a = 209/11
a = 19