Practice Problems

Answers

  1. Let's divide and then add to get \(p\) by itself.

    \(9(p-4)=-18\)

    \(\frac{9(p-4)}{9}=\frac{-18}{9}\)

    		 divide each side by 9
    \(p-4=\frac{-18}{9}\)  
    \(p-4=-2\)
    \(p-4+4=-2+4\)
    		 add 4 to each side to get \(p\) by itself
    \(p=2\)

    The answer:

    \(p=2\)

  1. Let's subtract and then multiply to get \(j\) by itself.

    \(\frac{j}{-2}+7=-12\)
    \(\frac{j}{-2}+7-7=-12-7\)
    		 subtract 7 from each side
    \(\frac{j}{-2}=-19\)
    \(\frac{j}{-2} \cdot -2 =-19 \cdot -2\)
    		 multiply each side by -2 to get \(j\) by itself
    \(j =38\)

    The answer:

    \(j=38\)

  1. Let's subtract and then multiply to get \(k\) by itself.

    \(\frac{k}{4}+3=14\)
    \(\frac{k}{4}+3-3=14-3\) subtract 7 from each side
    \(\frac{k}{4}=11\)
    \(\frac{k}{4} \cdot 4=11\cdot 4\) multiply each side by 4 to get \(k\) by itself
    \(k=44\)


    The answer:

    \(k=44\)

  1. Let's divide and then add to get \(q\) by itself.

    \(3(q-7)=27\)
    \(\frac{3(q-7)}{3}=\frac{27}{3}\) divide each side by 3
    \(q-7=9\)
    \(q-7+7=9+7\) add 7 to each side to get \(q\) by itself
    \(q=16\)

    The answer:

    \(q=16\)

  1. Let's divide and then subtract to get \(x\) by itself.

    \(-30=5(x+1)\)

    \(\frac{-30}{5}=\frac{5(x+1)}{5}\)

    		 divide each side by 5
    \(-6=(x+1)\)  
    \(-6-1=x+1-1\)
    		 subtract 1 from each side to get \(x\) by itself
    \(x=-7\)


    The answer:

    \(x=-7\)

  1. Let's subtract and then divide to get \(b\) by itself.

    \(-11b+7=40\)
    \(-11b+7-7=40-7\)
    		 subtract 7 from each side
    \(-11b=33\)
    \(\frac{-11b}{-11}=\frac{33}{-11}\)
    		 divide each side by -11 to get \(b\) by itself
    \(b=-3\)

    The answer:

    \(b=-3\)

  1. Let's add and then divide to get \(d\) by itself.

    \(41=12d-7\)
    \(41+7=12d-7+7\) add 7 from each side
    \(48=12d\)
    \(\frac{48}{12} =\frac{12d}{12}\) divide each side by 12 to get \(d\) by itself
    \(d=4\)


    The answer:

    \(d=4\)

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