Find 4 consecutive even integers where the product of the two smaller numbers is 72 less than the product of the two larger numbers.
Let the two smallest integers = x and x + 2
Let the two largest = x + 4 , x + 6
So
x(x + 2) + 72 = (x + 4) ( x + 6) simplify
x^2 + 2x + 72 = x^2 + 4x + 6x + 24 subtract x^2 from both sides and simplify
2x + 72 = 10x + 24 subtract 24, 2x from both sides
8x = 48 divide both sides by 8
x = 6
x + 2 =8
x + 4 =10
x + 6 = 12