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. ^^

2x + 1 < 5 solve the following inequality. then place the correct number in the box provided.

Adepartment store purchases screen-printed t-shirts at a cost of $5 per shirt. they mark up the price 150% (making the selling price 250% of the store's purchase price) and put them on the sales floor. every month that a t-shirt doesn't sell, the store reduces the selling price by 25%.

Which is a reasonable estimate of the amount of water in a small, inflatable pool used by children?