Solving exponential equations with logarithms

Lessons

1. Solve for $x$ , by converting from exponential form
   to log form:
   
   1. $y = 5 \cdot {2^x}$
      
   2. $6 \cdot {3^x} = 90$
      
2. Let's revisit the earlier example about Bianca saving up money to buy her dream car, Mini Cooper.
   Now we are ready to find out the exact amount of time it'll take Bianca to save up $30,000:
   On Bianca's 5-year-old birthday, Bianca gets a birthday gift of $100 cash from her dad.
   Bianca's dad promises to double her money yearly if Bianca plans to not spend the
   money but instead deposits it into "daddy-super-saving-account". Will Bianca be able
   to afford her dream car, Mini Cooper, worth $30,000 when she turns 16-year-old?