Ihave to combine all the variable but i don't understand how with the decimals

What are the soultion(s) to the quadratic equation 40- x^2=0

Huong is organizing paperback and hardback books for her club's used book sale. the number of paperbacks is 12 less than three times the number of hardbacks. huong had 162 paperbacks. how many hardback books were there?

Going from point a to point b, the cheetah traveled at an average rate of 70 mph. returning to point a, the cheetah traveled at an average rate of 40 mph. can we say that this cheetah’s average rate was 55 mph? uchet write an equation for the average rate for the trip. remember, the cheetah runs from point a to point b and back to point a. first leg of trip: second leg of trip: ⦁ the following equation represents the average rate for the trip. is this equation equivalent to the one you wrote above? explain why or why not.