Factorisation

Exercise 14.4

Find and correct the errors in the statement:

\[4(x - 5) = 4x - 5\]

What is known?

Incorrect mathematical statement.

What is unknown?

Correct mathematical statement.

Reasoning:

Solve L.H.S.

Steps:

\[{\rm{S}} = 4(x - 5) \ne \rm R.H.S.\]

The correct statement is \(4(x - 5) = 4x - 20\)

\[x(3x + 2) = 3{x^2} + 2\]

\[\begin{align} {\rm{L.H.S}} &= x(3x + 2)\\&= 3{x^2} + 2x\\ {\rm{L.H.S}} &\ne {\rm{R.H.S}} \end{align}\]

The correct statement is \(x(3x + 2) = 3{x^2} + 2x\)