5^2x-1=27.6
solve for x
Thank you, Michelle
I think you mean
52x-1 = 27.6
Take natural logs of both sides:
ln(52x-1) = ln(27.6)
Now use the rule ln(MN) = N·ln(M) on the left side:
(2x - 1)ln(5) = ln(27.6)
Let A = ln(5) and B = ln(27.6)
(If you have a TI graphing calculator,
a good idea here would be to store these
two logs as A and B)
(2x-1)A = B
A(2x-1) = B
2Ax - A = B
2Ax = B + A
Divide both sides by 2A
x = (B + A)/(2A)
Now replace A by ln(5) and B by ln(27.6)
x = [ln(27.6) + ln(5)]/[2·ln(5)]
x = 1.530737423
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Note: If the A and B above confuses you,
then go back to this step:
(2x - 1)ln(5) = ln(27.6)
find the logs on the calculator, and substitute:
(2x - 1)(1.609437912) = 3.317815773
1.609437912(2x - 1) = 3.317815773
3.218875825x - 1.609437912 = 3.317815773
Add 1.609437912 to both sides:
3.218875825x = 3.317815773 + 1.609437912
3.218875825x = 4.927253685
Divide both sides by coefficient 3.218875825
x = 4.927253685/3.218875825
x = 1.530737423
Edwin