3logbase5(x^2+9)-6=0

can somebody me solve this ? if you can, don't just say the answer, i want to understand how to do this so an explanation would come in handy and you. ^^

The sum of two numbers is 58. the first number is 8 less than half the second number. let  c  represent the first number. let  drepresent the second number. which statements about solving for the two numbers are true? check all that apply. the equation    represents the sum of the two numbers. the equation    represents the sentence “the first number is 8 less than half the second number.”the equation    represents the relationship between the two numbers. the equation    represents the sum of the two numbers. the number  d  is 14.the number  c  is 44.the number  c  is 14.the number  d  is 44.

How to do this , and can some one explain

The ivring berlin learning center would like a possible net profit of $650,000 on its new resource manual it sells to schools. the fixed costs for producing the manual are $780,000 and the variable cost per package is $19.85. if the estimated unit sales are 1,250,000 units, what selling price unit should the ivring berlin learning center try?