Question

3,125=5^-10+3x What does x equal

Answer 1

x = 30517578124/29296875

Explanation:

Solve for x:

3125 = 3 x + 1/9765625

Put each term in 3 x + 1/9765625 over the common denominator 9765625: 3 x + 1/9765625 = (29296875 x)/9765625 + 1/9765625:

3125 = (29296875 x)/9765625 + 1/9765625

(29296875 x)/9765625 + 1/9765625 = (29296875 x + 1)/9765625:

3125 = (29296875 x + 1)/9765625

3125 = (29296875 x + 1)/9765625 is equivalent to (29296875 x + 1)/9765625 = 3125:

(29296875 x + 1)/9765625 = 3125

Multiply both sides of (29296875 x + 1)/9765625 = 3125 by 9765625:

(9765625 (29296875 x + 1))/9765625 = 9765625×3125

(9765625 (29296875 x + 1))/9765625 = 9765625/9765625×(29296875 x + 1) = 29296875 x + 1:

29296875 x + 1 = 9765625×3125

9765625×3125 = 30517578125:

29296875 x + 1 = 30517578125

Subtract 1 from both sides:

29296875 x + (1 - 1) = 30517578125 - 1

1 - 1 = 0:

29296875 x = 30517578125 - 1

30517578125 - 1 = 30517578124:

29296875 x = 30517578124

Divide both sides of 29296875 x = 30517578124 by 29296875:

(29296875 x)/29296875 = 30517578124/29296875

29296875/29296875 = 1:

Answer: x = 30517578124/29296875

Answer 2

For this case:

We rewrite the equation as:

`5 ^ {- 10 + 3x} = 3.125`

We find ln on both sides of the equation to remove the exponent variable:

`ln (5 ^ {- 10 + 3x}) = ln (3,125)`

Applying properties of logarithm we have:

`(-10 + 3x) ln (5) = ln (3.125)`

We apply distributive property:

`-10ln (5) + 3xln (5) = ln (3,125)`

We clear the value of "x":

`3xln (5) = ln (3,125) + 10ln (5)\\x = \frac {ln (3.125)} {3ln (5)} + \frac {10ln (5)} {3ln (5)}\\x = \frac {ln (3.125)} {3ln (5)} + \frac {10} {3}`

ANswer:

`x = \frac {ln (3.125)} {3ln (5)} + \frac {10} {3}`