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Video transcript

a popular R&B brand recently returned from a successful three-city tour where they played to at least 120 so at least 120,000 people my brain immediately says that's greater than or equal to 120 thousand if they had an audience of 45,000 in Mesa and another 33,000 in Denver how many people attended their show in Las Vegas so let's say Las Vegas I'll just use L for Las Vegas so the number of people who attended the show in Las Vegas plus the number that attended the show in Mesa which is 45,000 plus the number of people that attended their show in Denver which is 33,000 those are our three cities right there Las Vegas Mesa and Denver that has to be at least 120 thousand people or another way interpreting that is greater than or equal to 120 thousand so to figure out how many people attended their show in Las Vegas we just solve for L on this inequality so if we simplify this right-hand side we get or sorry this left-hand side we get the number of people in Las Vegas plus what's forty-five thousand plus thirty three thousand that is 78 thousand plus 78,000 is going to be greater than or equal to 120 thousand now to isolate the L on the left hand side of the inequality we can subtract 78,000 from both sides so minus 78,000 minus 78,000 on the left hand side these cancel out and we're just left with the number of people who attended the show in Las Vegas is going to be greater than or equal to 120 thousand minus 78,000 so 120,000 minus 80,000 is 40,000 that's going to be another two thousand so the number of people attend Las Vegas is going to be greater than or equal to 42,000 people and we're done that's it