Introduction: Systems of Equations

​You recently received some birthday money, $130 to be exact. You count the number of bills you have and find that you have 17 bills, all either $10 or $5 bills.

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How many of each bill do you have?​

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Hint: Just try guessing and checking first!​

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Sometimes, in math, we are asked for two answers, like how many $5 bills AND $10 bills. Systems of equations are how we solve these problems.

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Systems of equations are two or more equations that have the same variables like:​

y=x+1

y=-2x+6​

which both have x and y​

Systems of equations are used when we are given two pieces of information and asked for two answers from it, like our first question.

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Solutions are where two lines intersect on a graph and these are our answers.

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The solution here is (-1,3) because that is where the lines intersect!​

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​Solutions=answers

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