Friday 14 July 2017

EXPONENTIALS 7


If 810 = 32a-2; find a

Solution

810 = 32a-2 

(23)10 = (25)a-2 

230 = 25(a-2) 

230 = 25a-10

230 = 25a-10      [Same bases both sides, cancel out]

30 = 5a – 10

30 + 10 = 5a

40 = 5a

40 = 5a
5      5

8 = a

Hence a=8

TRY THIS……………………….


If 47 = 64y-2; find y

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