Danny and his brothers age

Question

Danny stated that his older brother is three more than twice his age and that four years ago his brother was four times as old as him.

a) Create a table and write algebraic expressions that represent the current and the age four years ago for both danny and his brother

b)How old was danny and his brother 4 years ago?

For a I made Danny d, and then got the expression 2d+3 but I cannot figure out the expression for age after four years, any help with solving (b) will be appreciated as well

Answer 1

B = 3+2D

today

but 4 years ago

B-4=4(D-4)

B= 4D-16+4

B =4D -12

set the 2 expressions for B equal

3+2D = 4D-12

2D = 15

D = 15/2 = 7 1/2 years old today

B =3+2(15/2) = 18 years old today

four years ago, D=3 1/2 and B = 14