First and last terms of the given equation are perfect squares. They can be written as
(4p^2)^2+ 2.(4p^2).5+(5)^2
It's like identity 1: (a+b)^2=a^2+2ab+b^2
So a=4p^2 and b=5
Therefore it is equal to (4p^2+5)^2
Let us represent number of one person tubes rented by x and, number of cooler tubes rented by y As per the situation, total tubes are 15, hence x + y = 15 equation 1 Also, total expenditure on tubes is $270, therefore 20x + 12.5y = 270 equation 2 Linear equation written above, equation 1 and equation 2 represent given situation. Now, let us solve these equations to find number of tubes rented Multiplying equation 1 by 20 and subtracting equation 2 from it, we get 20x + 20y - 20x -12.5y = 300 - 270 7.5y = 30 y = 4 and from equation 1, x + 4 = 15 gives, x = 11 Therefore, number of person tubes = 11, number of cooler tubes = 4
This will be simple since They are both solved for Y. :) put them across from each other (in parenthesis if you want to show which one was substituted). So we have ( x + 4 )= -2x - 2. Next subtract the 4 from both sides and add 2x to each side. Now we have 3x = -6. Divide by 3 and get X=-2. Plug X into an original equation and solve for Y. y = (-2) + 4. Y=2 (2, 2)