I need help this is very hard please

7 + 6 = 9 + 4

16 - 7 = 3 + 6

20 x 6 = 60 x 2

2 x (3 + 5) = 20 - 4

3 + (3 x 6) = 3 + 3 + 15

Given that, we have to find the missing numbers in each equation

Let the unknown be "x"

7 + x = 9 + 4

Solve the right side of equation, 9 + 4 = 13

7 + x = 13

x = 13 - 7

x = 6

Let the unknown be "x"

16 - 7 = 3 + x

Solve the left side of equation, 16 - 7 = 9

9 = 3 + x

x = 9 - 3

x = 6

Let the unknown be "x"