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Writing Algebraic Expressions

Added Sep 29, 2023 •

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writing algebraic expression you know a lot of students when they open up a math problem and it's a word problem they don't even know where to start and then kind of a day already give up before they even tried so today we're going to break down a word problem into algebraic expressions and then solve it so here's a sample problem I have Eric and $7 more than Chris is 3 times as much money is Chris Watt has $5 less than twice as much as put together they have $72 how much money does each person have kind of overwhelming problem what we have Eric Chris the Ambassador and we have one what other information do we have we know that all together they have $70 set the add up all the money that they have it to come to $72 now you want to look for where to start everything here is about Chris more than Chris less than Chris as much as quick so we're going to make him the variable my personal favorite variable is X by the way she's at but you can use any letter of the alphabet $7 more than so whatever Chris has I'm going to add 72 it a sticker has three times as much money so whatever amount Chris has we're going to multiply it by 3 so that would get that expression with the 3x now here's the tricky part why has $5 less than twice as much Google take a $5 less okay well that's my spot and then twice as much but this is incorrect because $5 less than means the $5 away from the 2X and if you don't put that correctly your whole problem will be wrong so $35 less than twice as much okay so these are the directions to represent how much they have here is the total we just added all together and do a simple equation Eric is x + 7 Chris is at Massacre is react 1 is 2x - 5 and when you add all that up we get 72 circle equation x + at term for example we have have a 7 and I - 57 - 5 is too so I'm going to bring that down got rid of it why do we have left we have a 2X 3M Annex Annex you can add all those terms together because it's the same variable there's an invisible one in front of these actors. There's no number or coefficient in front of the letter there's an if there's an invisible one so is 1 + 1x + 2x + 3x is 5x + 2 + 7x + 2 equal 72 equation and if you remember from equation do anything you want to one side as long as whatever you do to one side you have to do to the other so if I if I subtract 2 from this I had to distract you from this side what do we have left 7x equals 70 how do we get rid of multiplication division CD by both sides by 7 or if you think about it 7 times something equals 7010 not done a lot of students will do this equal 10 done you're not done why because what yet look back in the original question how much money does each person have the Nexus 10 that means Chris has $10 how much would Eric have 7 how much would a Shakur have 30 how much would one have you put the 10 in for the X 10 * 2 is 20 - 5 is 15 and here's the steps your Math teachers will appreciate it if you do go back and check it added together did he goes out 72 so there's an example of how to take a word problem break it down into algebraic expression and then stop

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Writing Algebraic Expressions

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