Question 1043601
Solve
a)7^2x+1 = 4^x-2
What are the exponents?
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b) 4^x = 3+18(4^-×)
Multiply thru by 4^x
4^(2x) = 3*4^x + 18
4^(2x) - 3*4^x - 18 = 0
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Sub u for 4^x
4u^2 - 3u - 18 = 0
*[invoke solve_quadratic_equation 4,-3,-18]
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Ignore the negative solution.
4^x =~ 2.52921
x*log(4) = log(2.52921)
x = log(2.52921)/log(4)
x =~ 0.66934
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C) 9=logbase5 (x+100) +6
{{{3 = log(5,(x+100))}}}
{{{log(5,5^3) = log(5,(x+100))}}}
x+100 = 125
x = 25