Answer:
Perimeter= 12y units
3y(4) = 12y
Step-by-step explanation:
3y + 3y + 3y + 3y= 12y
Answer:
a) 
b) 1.5 hours after thickness will be 2 inches.
Step-by-step explanation:

Answer:
x + 3y = 15
Step-by-step explanation:
Line is passing through the points 
Slope of line (m)= (2 - 4)/(9 - 3) = -2/6 = -1/3
Equation of line in point-slope form is given as:

Plugging the values of
in the above equation we find:




This is the required equation of line in the form 
The total cost that a customer should incur in its dealings with company A should be,
c = 50t + 100
For company B
c = 60t + 80
Equating these two charges
c = 50t + 100 = 60t + 80
Thus, the answer is the fourth choice.