Given the expression 
Take a logarithm
from both side of the given expression:

From the property
you have that

Then

Answer: correct choice is C
3x+1/10=x-1/7
subtract 1/10 from both sides
3x=-1/7-1/10+x
subtract x from both sides
2x=-1/7-1/10
add -1/7 and -1/0
1/7=10/70
1/10=7/70
-10/70-7/70=-17/70
2x=-17/70
divide by 2 ro multiply by 1/2
x=-17/140
If you plug the values for a, b, and c into the Pythagorean Theorem, you can get x alone to figure out the side lengths:
x² + 3x² - 1² = 3x² + 1²
Combine like terms
4x² - 1² = 3x² + 1²
Subtract 3x² from both sides
x² - 1² = 1²
Simplify 1²
x² - 1 = 1
Add 1 to both sides
x² = 2
Square root both sides
x = 1.41421
Then, simply plug in that number for x on each side! It comes out to a weird number, but I don't see any other way to solve it...
Hope this helps :)
Answer: 45
Step-by-step explanation:
60 minus 15 equals 45( there is 45 girls)