Anonymous

Without algebra, just think of the integer factors of 39. There are only a few cases to consider: -39 × -1 -13 × -3 3 × 13 1 × 39 Only one pair has the larger number being one more than four times the other. 4(3) + 1 = 13 Answer: 3 and 13

Anonymous

b(4b+1) = 39 4b^2+b-39 = 0 Use the quadratic formula b = [-1±√625]/8 = 3 (the only integer solution) a = 13 Answer 3 & 13

Anonymous

3,13 because those are the factors of 39 and it works. If you need algebra: y = 4x +1 xy = 39 x(4x+1) = 39 4x^2 +x -39 = 0 (4x +13)(x -3) x = -13/4 ; 3 Reject -13/4 as not an integer x = 3 y = 4(3) +1 = 13

Anonymous

x=4y+1 xy=39 -->x=13 , y=3