Question 718819
Sure
{{{  5 + x = 68 }}}
If you had $5, how much more do you need 
so you will have $68
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{{{ 2x + 2 }}}
This is not an equation, since there is no = sign,
but it is an expression with an unknown, {{{x}}}
You could say:
If {{{ x }}} is my age now, and
If my sister is twice as old as me, how old
will my sister be in 2 years?