Rosa brought d drawings to an art show. After selling 15 of them, she had 38 left.

Let x be the # of drawings Rosa brought to the show. After selling 15 of them, she had 38 left. Thus, x - 15 = 38. To solve for x, add 15 to both sides:

x - 15 + 15 = 38 + 15 = 53. Rosa originally had 53 drawings to sell.

She originally had 51 paintings