Solve for a
a=-\frac{7\sqrt{2}}{2}+22\approx 17.050252532
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\frac{\left(a-8\right)\left(\sqrt{2}-3\right)}{\left(\sqrt{2}+3\right)\left(\sqrt{2}-3\right)}=a-15
Rationalize the denominator of \frac{a-8}{\sqrt{2}+3} by multiplying numerator and denominator by \sqrt{2}-3.
\frac{\left(a-8\right)\left(\sqrt{2}-3\right)}{\left(\sqrt{2}\right)^{2}-3^{2}}=a-15
Consider \left(\sqrt{2}+3\right)\left(\sqrt{2}-3\right). Multiplication can be transformed into difference of squares using the rule: \left(a-b\right)\left(a+b\right)=a^{2}-b^{2}.
\frac{\left(a-8\right)\left(\sqrt{2}-3\right)}{2-9}=a-15
Square \sqrt{2}. Square 3.
\frac{\left(a-8\right)\left(\sqrt{2}-3\right)}{-7}=a-15
Subtract 9 from 2 to get -7.
\frac{a\sqrt{2}-3a-8\sqrt{2}+24}{-7}=a-15
Apply the distributive property by multiplying each term of a-8 by each term of \sqrt{2}-3.
\frac{a\sqrt{2}-3a-8\sqrt{2}+24}{-7}-a=-15
Subtract a from both sides.
a\sqrt{2}-3a-8\sqrt{2}+24+7a=105
Multiply both sides of the equation by -7.
\sqrt{2}a-3a+7a-8\sqrt{2}+24=105
Reorder the terms.
\sqrt{2}a+4a-8\sqrt{2}+24=105
Combine -3a and 7a to get 4a.
\sqrt{2}a+4a+24=105+8\sqrt{2}
Add 8\sqrt{2} to both sides.
\sqrt{2}a+4a=105+8\sqrt{2}-24
Subtract 24 from both sides.
\sqrt{2}a+4a=81+8\sqrt{2}
Subtract 24 from 105 to get 81.
\left(\sqrt{2}+4\right)a=81+8\sqrt{2}
Combine all terms containing a.
\left(\sqrt{2}+4\right)a=8\sqrt{2}+81
The equation is in standard form.
\frac{\left(\sqrt{2}+4\right)a}{\sqrt{2}+4}=\frac{8\sqrt{2}+81}{\sqrt{2}+4}
Divide both sides by \sqrt{2}+4.
a=\frac{8\sqrt{2}+81}{\sqrt{2}+4}
Dividing by \sqrt{2}+4 undoes the multiplication by \sqrt{2}+4.
a=-\frac{7\sqrt{2}}{2}+22
Divide 81+8\sqrt{2} by \sqrt{2}+4.
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