The total cost of water heater including a 7% sales tax is 524.30 what is the cost of the water heater without the tax

Anyone know? will mark brainliest if you're correct!

What is the answer to the question 5x+2x

Two poles, ab and ed, are fixed to the ground with the of ropes ac and ec, as shown: what is the approximate distance, in feet, between the two poles? 6.93 feet 8.66 feet 12.32 feet 15.59 feet