Problem : Solve for y: 7 + y = 13

y = 6

Problem : Solve for m: 17 + m + 13 - 20 = 15

m = 5

Problem : Solve for k: 3k + 2 = 11

k = 3

Problem : Solve for c: (6 + c)/2 = 5

c = 4

Problem : Solve for u: 18 - u = 5

u = 13

Problem : Solve for q: 3×(9 - q) = 27

q = 0

Problem : Solve for j: 14 + j = 7

j = - 7