Answer:
a = 20
Step-by-step explanation:
1/2a - 4 = 6
+4 +4
--------------------
1/2a = 10
*2 *2
---------------------
1a = 20
/1 /1
----------------------
a = 20<em> -------------------> answer</em>
m=81
14 x 1.5 = 21
54 x 1.5 = 81
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