Ming throws a stone off a bridge into a river below. The stone's height (in meters above the water), xxx seconds after Ming threw it, is modeled by:
h(x)=-5(x-1)^2+45h(x)=−5(x−1)
2
+45h, left parenthesis, x, right parenthesis, equals, minus, 5, left parenthesis, x, minus, 1, right parenthesis, squared, plus, 45
What is the maximum height that the stone will reach?

people went from manufacturing one object at a time by hand to manufacturing many objects in factories

a 4/6 = 9/12   not proportional

step-by-step explanation:

to find which are not proportional, we can use cross products

if it is true, they are proportional.   if it is not true, they are not proportional.

a 4/6 = 9/12

4* 12 = 6*9

48 = 54

not this is not proportional  

b 2/3 = 12/18  

2* 18 = 3 * 12

36 = 36

this is proportional

c 5/4 = 10/8  

5*8 = 4*10

40 = 40

this is proportional

d 7/5 = 35/25

7*25 = 5 * 35

175 = 175

is proportional