We have to write an equation from the word problem,
Four subtracted from the product of 5 and a number is 51
Let's break it down:
--- product of 5 and a number can be written as,
--- four subtracted from "product of 5 and a number" can be written as,
^^ All this is equal to 51, so we can write,
To find the unknown number, we solve the above equation. The steps are shown below: