human
Solve one-step linear equations requiring addition or subtraction, with all positive integers Isaac is solving an equation. This is the left-hand side of two lines of working from Isaac's book. Isaac always records what operation he has done to both sides of the equation.
What operation should replace the star? ![The image shows two lines of working and an arrow from the top line to the bottom line with a star next to it where the operation would be labelled. The top line of working is x + 7 = ..., and the bottom line is x = ...]() \( \div 7 \)
gpt
Thinks the inverse of addition is division