1/4(a + 10) =2a -4 multiply both sides by 4 to clear the fraction on the left
a + 10 = 8a - 16 subtract a from both sides and add 16 to both sides
26 = 7a divide both sides by 7
26 / 7 = a
\(\frac{1}{4(a+10)}=2a-4\\ \frac{1}{a+10}=8a-16\\(8a-16)(a+10)=1\\ 8a^2+64a-160=1\\ 8a^2+64a-161=0\\ a=\frac{-64\pm\sqrt{64^2-4(8)(-161)}}{2(8)}\\ \;\;=\frac{-64\pm68\sqrt2}{16}\\ \;\;=-4\pm\dfrac{17\sqrt2}{4}\)
\(\frac{1}{4}(a+10)=2a-4 \\a+10=8a-16\\7a=26\\a=\dfrac{26}{7}\)
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