Given that: log10 (7a + 2) = log10 (a – 4) + 1, what is the integer value of ‘a’?
Given that: log10 (7a + 2) = log10 (a – 4) + 1, what is the integer value of ‘a’? Correct Answer 14
GIVEN:
log10(7a + 2) = log10(a – 4) + 1
CONCEPT:
1 = log1010
FORMULA USED:
Property:
loga(P × Q) = logaP + logaQ
CALCULATION:
log10(7a + 2) = log10(a – 4) + 1
⇒ log10(7a + 2) = log10(a – 4) + log1010
⇒ log10(7a + 2) = log10
After comparing:
7a + 2 = 10(a – 4)
⇒ 3a = 42
⇒ a = 14
∴ Integer value of a = 14
মোঃ আরিফুল ইসলাম
Feb 20, 2025