Write the equation based on the picture and calculate the mass of the unknown package.

Answer:
5x + 4 = 4x + 7
x = 3
Step-by-step explanation:
Let's call the mass of the unknown package "x". The equation is:
2+2 + x+x+x+x+x = x+x+x+x + 2+5
5x + 4 = 4x + 7
Now let's solve for x
5x + 4 = 4x + 7
x + 4 = 7
x = 3