7. To find the area of a triangle you use base x height /2. so the base is 10 and the height is 25 so you do 10 x 25 first which is 250 then divide by 2 which gives you 125 so the area of each pennant is 125 cm^2 ( the ^2 means squared)
8. To find the area of a square you do length x Width. Since for a square all sides are the same the length AND the width are both 450cm. Now you just do 450 x 450 which gives you 202,500 cm^2. BUT it asks for an answer written in SQUARE METRES so you have to change 450cm to metres making it 4.5 metres x 4.5 metres = 20.25 SO THE REAL ANSWER IS 20.25 M^2
Hope this helps you out!