Question

Solve the following algebraic expressions by both trial and error method and balancing equation.
$x+11=21$

Answer 1

Given $x+11=21$

Let $x=1,LHS=1+11=12,RHS=21$

$LHS\ne RHS$

Let $x=10,LHS=11+10=21,RHS=21$

As $LHS=RHS$

By trial and error method

So $x=10$

By balancing equation

$x+11=21⟹x=21-11=10$