Please solve this both problems please chapter exponents and powers class 8
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Answer:
29. x = 3
30. x = 10^4
Step-by-step explanation:
29. 5^x + 15(5^0) + 5² + 4(5^x) = 665
=> 5^x + 15(1) + 25 + 4(5^x) = 665 (x^0 = 1)
=> 5^x + 15 + 25 + 4(5^x) = 665
=> 5^x + 40 + 4(5^x) = 665
=> 5^x + 4(5^x) = 665 - 40 => 625
=> 5(5^x) = 625
=> 5^x = 625/5 => 125
=> 5^x = 5³
Comparing, x = 3.
30. 800 = 8*(10^8)*(x^{-3/2})
=> 800/8*10^8 = x^(-3/2)
=> 100/10^8 = 1/√x³
=> 10²/10^8 = 1/√x³
=> 1/10^6 = 1/√x³
=> 1/10^12 = 1/x³ (Squaring both sides)
=> 1/(10^4)³ = 1/x³
Comparing, x = 10^4.
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