2x + 5 = 192x + 5 - 5 = 19-52x = 142x/2 = 14/2x = 7
1
The answer is 672.
19 plus 19 is 38.
491
19 + 19 + 4 + 4 = 46
21+21+19+19=80
19+19+9 = 47
19 + (44 + 23) = (19 + 44) + 23
25 plus 21 plus 19 is equal to 65.
There are 19 floors plus the summit
There are many solutions: (1, 2, 19), (-1, -2, 19), (1, -2, -19), etc or (7, 11, 14) and its variants.