"Do you understand? The following are the assumptions of the equation.
If you choose the right question, you will get 4 points, and if you choose the right question, you will get 4x.
Deduct 1 point for not choosing or choosing the wrong question, and the deduction will be (25-x)* 1, abbreviated as (25-x);
So according to the meaning of the question, the equation is 4x-(25-x)=85.
Then remove the brackets of 4x-25+x=85.
That is 5x=85+25.
That is 5x= 1 10.
(This formula shows that 5 times x equals 1 10, so x equals110 divided by 5).
x= 1 10/5=22