Answer
$x=-\dfrac{23}{67}$
Work Step by Step
Using the properties of equality, the solution to the given equation, $
4.2x+3.5=1.2-2.5x
$, is
\begin{array}{l}\require{cancel}
4.2x+2.5x=1.2-3.5
\\\\
6.7x=-2.3
\\\\
x=-\dfrac{2.3}{6.7}
\\\\
x=-\dfrac{2.3}{6.7}\cdot\dfrac{10}{10}
\\\\
x=-\dfrac{23}{67}
.\end{array}
