What is the solution set for the open sentence with the given replacement set? 3x + 4 = 19, {4, 5, 6, 7}

3x + 4 = 19
3(5) + 4 = 19
15 + 4 = 19
19 = 19

so answer x = 5

I’m pretty sure it’s i think : /

Best answer that i found on yahoo ok   set :   x= length of 2nd piece in cm  x- 3= length of 1st piece in cm  x-4= length of 3rd piece in cm  then since you know they all came from the 20 cm ribbon you add them together and set them equal to 20x+ x-3 +x-4 = 20  3x - 7= 20  3x= 27  x= 9  the shortest piece is the third piece which is x- 4  x-4  9-4 = 5  the length of the smallest piece is 5 cm.  the other lengths are  9 cm  6 cm