7. The area of a rectangle is equal to the length l multiplied by the width w .
Write an expanded expression for the area of the following rectangles.
(i) (ii)
(iii) (iv)
Length l (6x − 5)
(12m − 6) (x − 5)
(n + 10)
Width w (x − 4)
(2m + 5) (x – 5)
(n − 10)
8. The area of a triangle is equal to half the base b , multiplied by the perpendicular height h .
Write an expanded expression for the area of the following triangles.
Base b (i) (ii)
(iii) (iv)
(12x − 5) (22x + y) (2x − 3) (t + 8)
Perpendicular height h
(5x − 3) (4x + 5y) (5x + 10) (t + 8)
Taking it FURTHER
9. Darragh has to buy x footballs at €50 each and y sliotars at €5 each. Write an expression for the total value of the footballs and sliotars that Darragh needs to buy.
10. Emily has 4n + 6 towels to place on each fl oor in her hotel. If there are 2m + 10 fl oors in the hotel, write an expression for the total number of towels that Emily requires for all the fl oors in her hotel.
20.5 Factorising using a factor common to all terms in an expression