Why can you not divide expressions by common factors?

With equations, e.g. 4x = 12, the 4x variable has a given value. This means you can apply the same changes to both sides (at the same time). For example, both sides can be divided by 4 to give x=3
However expressions, e.g. 4x + 12, do not have an equal sign. This means the value of x is unknown and is simply a variable and the expression cannot be changed. Instead the expression can be simplified, for example by factorisation 4(x+3).

FM

Related Maths GCSE answers

All answers ▸

How can I find the angle between 2 vectors?


Does the function y=x^3+x+(x^2+1)e^x have a horizontal tangent?


Find the coefficient of the constant term of the expression (2x+1/(4x^3 ))^8


Northern Bank has two types of account. Both accounts pay compound interest. Cash savings account: Interest 2.5% per annum Shares account: Interest 3.5% per annum Ali invests £2000 in the cash savings account. Ben invests £1600 in the shares account.