Hi there! Hopefully this helps!
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Answer: j = <u>-7</u>
You can also <u>rewrite</u> the equation(replace "j" with the answer):
-1.68<u>(-7)</u> + 1.24 = 13.
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<em>How I solved it:</em>
-1.68j + 1.24 = 13.
<em>We </em><u><em>subtract 1.24</em></u><em> from </em><u><em>both</em></u><em> sides.</em>
-1.68j = 13 - 1.24
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-1.68j = 13 - 1.24
<em>We </em><u><em>subtract 1.24 from 13</em></u><em> to get 11.76.</em>
-1.68j = 11.76
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-1.68j = 11.76
<em>We then </em><u><em>divide both sides</em></u><em> by -1.68.</em>
j = 
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<em>Expand </em>
<em> ≈ -7 by </em><u><em>multiplying both the numerator and the denominator</em></u><em> by 100.</em>
j = 
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<em>Divide 1176 by -168 to get -7.</em>