As we know that the area of a rectangle is -
length × Breadth
So, here length = (3n+1)
Breadth = (2n-5)
Area of rectangle
= (3n+1)(2n-5)
= 3n(2n-5)+1(2n-5)
= 6n² - 15n + 2n - 5
= 6n² - 13n - 5
Answer) Area of rectangle is 6n² - 13n - 5
-6a-12b+18c+24d-8a-3b+4c+2d=-6a-8a-12b-3b+18c+4c+24d+2d=
=-14a-15b+22c+26d
