4.5×1.5 = _______
12.5×2.4
Multiply 125×24
11 21 25× 24–––––– 1 500 2 50–––––3000–––––
shift by two decimal places;we have
12.5×2.4=30–––
Question 84 (xi)
Simplify
(4.5a+1.5b)2+(4.5b+1.5a)2
(4.5)2−(1.5)2