To write an expression in expanded form, simply times the number outside the bracket with the numbers/letters inside the bracket.
I'll show my working out.
4(X + Y)
times four by the letters inside the bracket.
(4 x X) + (4 x Y)
this leaves us with
4x + 4y
8(a + 3b) --> (8 x a) + (8 x 3b) = 8a + 24b
3(2X + 11Y) --> (3 x 2X) + (3 x 11Y) = 6x + 33y
9(7a + 6b) --> (9 x 7a) + (9 x 6b) = 63a + 54b
c(3a + b) --> (c x 3a) + (c x b) = 3ac + bc
y(2x + 11z) --> (y x 2x) + (y x 11z) = 2xy + 11yz
remember when you times 'letters' (eg. x,y,z) together, you simply write them next to each other (eg. a x b=ab).
