Swtich from fractional index to square root:
Square both sides:
Expand (FOIL Method):
Hehe, don't complicate yourself with logs. This is just a SAT question. Basically, what you do is try to get both bases to be the same. We can switch 8 to 2^3, so we get:
They're equal to each other, so the exponents has to be the same. Thus:
3. Percentage increase, very simple. What you do is subtract Elina's height at age of 6 from height at age of 12 and divide by height at age of 6.