Question

Brad wants to buy flowers for his friend with $39 the daises are $1 each and the roses are $3 each he buys 3 more daises then roses how much did the roses cost?

Answer 1

d+3r=39
d=r+3

(r+3)+3r=39 (Distribute r+3 with 1) Exp. 1(r) 1(3)
r+3+3r=39 (Combine like terms) Exp. r+3r=4r
4r+3=39 (Bring down -3 because the positive changes to a negative)
    -3   -3
4r/4 = 36/4 (Now you bring down 4 and divide it to 36)
r=9
________________________________________________________

So he bought 9 roses at $3 each so 9 x 3 is 27, so your answer is $27 or just 27 if this is on Plato.