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the speed of sound is approximately 768 miles per hour when an object travels faster than the speed of sound it creates a sonic boom and there's actually a whole video on how sonic booms are created on Khan Academy I encourage you to watch it it's actually fascinating but anyway back to this question write an inequality to represent s the speeds at which a moving object creates a sonic boom so what has to let's write an inequality let's suppose to do what they told us to s LCS has to be they say when an object travels faster than the speed of sound so our speed has to be greater than the speed of sound our speed has to be greater than the speed of sound which is 768 miles per hour so s has to be set greater than 768 now another way we could have written that is that 768 needs to be less than s we could have written 768 needs to be less than s that's another way we could write it in either case our speed is going to be greater than 768 miles per hour we check our answer let's do a few more of these to cook a steak to medium-rare it needs to have an internal temperature of 135 degrees Fahrenheit a lower internal temperature will under cook the steak write an inequality to represent all of the possible temperatures T of an undercooked steak well to be an undercooked steak your temperature is going to be less than 135 degrees so your temperature T is going to be less in you could either just use the left hand less than on your keyboard or you could click over here on less than your temperature is going to be less than 135 we're assuming your temperatures in Fahrenheit degrees so your temperatures but needs to be less than Fahrenheit less than 135 degrees if you are going to have an N undercooked steak so we've got that one right let's do let's do a couple more or well let's do one more Simone is going snowboarding is going snowboarding tomorrow if the temperature is equal to or colder than five degrees Celsius write an inequality to represent the temperatures at which Simone will go snowboarding so you might want to say you might want to say oh well maybe you know T is less than five degrees remember they're telling us that the temperature is equal to or colder so she's even willing to go snowboarding if it's less than or equal to five degrees so instead of just saying less than let's say less than or eat whoops let's say less than let's say less than or equal to five degrees so this inequality represented here this shows us all of the temperatures ne all of the temperatures at which she is willing to go norm no snowboarding and check our answer and we got it right