+0  
 
0
579
2
avatar

how do I solve 1/4(a + 10) =2a -4

 Jul 16, 2016
 #1
avatar+129841 
+5

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

 

 

 

cool cool cool

 Jul 16, 2016
 #2
avatar+9665 
0

\(\frac{1}{4(a+10)}=2a-4\\ \frac{1}{a+10}=8a-16\\(8a-16)(a+10)=1\\ 8a^2+64a-160=1\\ 8a^2+64a-161=0\\ a=\frac{-64\pm\sqrt{64^2-4(8)(-161)}}{2(8)}\\ \;\;=\frac{-64\pm68\sqrt2}{16}\\ \;\;=-4\pm\dfrac{17\sqrt2}{4}\)

 

 

 

 

 

 

 

 

 

\(\frac{1}{4}(a+10)=2a-4 \\a+10=8a-16\\7a=26\\a=\dfrac{26}{7}\)

.
 Jul 17, 2016

0 Online Users