Consider a rectangle of length l inches and width w inches. find a formula for the perimeter of the rectangle. use upper case letters. p = l+l+w+w (b) if the length and width of the rectangle are changing with respect to time, find dp dt . use dl dt and dw dt and not l ' and w ' . dp dt = 2( dl dt)+2( dw dt) (c) suppose the length is increasing at 2 inches per hour and the width is decreasing at 3 inches per hour. how fast is the perimeter of the rectangle changing when the length is 40 inches and the width is 104 inches?

to find the perimeter of the rectangle this is the expression:

x-9+x-9+3x-4+3x-4=138

if we simplify it:

8x-26=138

remember, 138 is what it all adds up to

the length is 11.5cm

the width is 57.5cm

the area is 661.25cm^2

the answers might not be correct use at own risk

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

the square root of 16 is 4.

4*4 = 16