Answer:
X = (J+M)/K
Explanation:
Undo what has been done to the variable, in reverse order. The variable has been multiplied by K and M subtracted from the result. So, we first add M (to undo the subtraction), then we divide by K (to undo the multiplication).
KX = J +M . . . . . . M added to the given equation
X = (J + M)/K . . . . the result of that is then divided by K
___
Since these are all capital letters, we might assume they represent vectors and/or matrices. If so, the "divide by K" step needs to be "multiply on the left by K^-1, the matrix inverse of K."
Then your solution looks like
X = K⁻¹·(J + M)