Solve |x + 5| < 9
if a>0 and you have |f(x)|<a then you do -a<f(x)<a if a>0 and you have |f(x)|>a then you do f(x)<-a or f(x)>a
this is a formula for you
your f(x)=x+5
which of formulas will you use above 1st one or 2nd one?
1st One ?
\(\bf |x + 5| < 9\implies \begin{cases} +(x + 5) < 9\implies x + 5 < 9 \\ \quad \\ \bf -(x + 5) < 9\implies x + 5 > -9 \end{cases}\) recall that in an inequality, when you multiply by a negative value, you have to \(\bf flip\) the inequality sign
right so you solve -9<x+5<9 and you are done
or you can view it like this:\[-9<|x+5|<9\]
i mean without the absolute parentheses: ( and solve two inequalities at once)\[-9<x+5<9\]
how do i solve it ? Im Lost sorry
you have to solve for x, that means leave x alone. so you have to get rid off everything else that stay with x
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