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Current time:0:00Total duration:4:17

Video transcript

Leena was watching a football game the team she was cheering for gained six yards on one play it lost eight yards on the next play it lost another two yards on the following play Leena wants to know what her team's net change in field position was after these three plays which of the following equations matches the situation above so let's think about it the team she was cheering for first they gained six yards so that's positive six yards then it then they lost eight so it would be six minus eight and then it lost another two so six minus eight minus two this is six minus eight but then plus two so this isn't right this is six plus negative eight which is equivalent to six minus 8 plus negative two so this would be equivalent to six minus eight minus two or another way to think about it they gained six yards then they lost eight yards and then they lost another two yards so definitely go with that one let's keep going Eddie and Fran are scuba-diving Eddie is 35 meters below the surface of the water and Fran is 8 meters directly above him the following situation describes this or the following equation describes this situation so let's see Eddie is 35 meters below the surface of the water so when we're below the surface that we're coming or the more below the surface we are the more negative I guess is is what we're doing here so if we're at the surface of the water you would be at 0 meters and they tell us Fran is 8 meters above him so we're taking we're taking Eddie's depth at 35 meters and then Fran is 8 meters above so we're adding 8 to figure out Fran's depth of negative 27 meters notice this is 8 meters above Eddie's depth so negative 27 is Fran's depth she is 27 meters below the surface of the water so select all that apply Fran is 27 meters below the surface of the water yeah that's what we just talked about if you if you if your if your depth is or I guess you can say you're if you're if you're at a negative here at negative 27 that means 27 meters below the water if you were at positive 27 that means you're 27 meters above the water so that's what they're telling us frans position relative to the surface of the water is negative 27 meters yeah I think that's a reasonable way to say it it's a little bit it's a little bit more confusing but yeah she is negative 27 meters below the surface of the water which we just set up here so I think that's fair enough to say that as well let's do one more Fred's basement is flooded the basement floor is three point four meters below the ground floor our that makes sense that the basement is below the ground three point four meters the water is 1.2 meters high the following equation describes the situation so negative 3.4 that's that's where the floor of the basement is it's three point four meters below the ground floor so the ground floor would be zero so it's three point four meters below the ground floor so that's the negative three point four but then the water is 1.2 meters the top of the the surface of the water is 1.2 meters above the floor of the basement so this negative 2.2 is how high the surf the top of the water is so what does negative 2.2 tell us well the top of the water is 2.2 meters below the ground floor yep that's right the water is 1.2 meters above the floor of the basement which is negative 2.2 meters and this is all relative to the ground floor so if the ground floor is zero the top of the water is negative 2 point 2 which means at the top of the water is 2.2 meters below that's what the negative tells us below the ground floor the water is 2.2 meters deep no that's not right they tell us that the water is 1.2 meters high or 1.2 meters deep so that's not right and we're not gonna click none of the above because we definitely found we found an answer