3 times x minus y is 5 times the sum of y and 2 times x

3 times x minus y is 5 times the sum of y and 2 times x

Take this algebraic expression in pieces:

3 times x:
3x

Minus y means we subtract y from 3x
3x - y

The sum of y and 2 times x mean we add y to 2 times x
y + 2x

5 times the sum of y and 2 times x:
5(y + 2x)

The word is means an equation, so we set 3x - y equal to 5(y + 2x)
3x - y = 5(y + 2x)