Let Y be the number we want and x represent the unknown value.

A)

Value we want = Y

Unknown = x

condition = three more than half of a number

*So we can write the algebraic expression as;*

*Y = (x/2)+3*

B)

Value we want = Y

Unknown = x

condition = double a quantity increased by nine

*So we can write the algebraic expression as;*

*Y = 2x+9*