Unit+6+-+System+of+Equations

﻿Here is a link for an explination of substitution: []

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Alright here we go!!! Solving Systems of Equations Stratagies: Name: Substitution Steps: 1. Isolate a variable with a coeficient of 1 by rearranging the equation. 2. Substitue the expression into the other equations for the isolated variable 3. Solve the equation 4. Substitute you arnswer back into the isolated equation and solve for the other variable. Example: Felix and Fay have a total of $2000. Felix has $250 more than fay. How much does Felix have? How much does Fay have? Equation 1: x+y=2000 Equation 2: x=250+y x+y=2000 -x -x y=2000-x - x=250+(y) x= 250 + (2000 - x) x=2250 - x  2x=2250 x=1125 - 1125= 250 + y  875=y (1125,875)

Solving Systems of Equations Stratagies: Name: Graphing Steps: 1. Create a table of at leaste three point by choosing smart x values and solve for y 2. Use y- intercept and rise over run 3. Calculate intercepts using intercept table. Example; Incert both equations into calculators y= button and then graph - Solving Systems of Equations Stratagies: Name: Elimination Steps: 1. To arrange the equations with like terms in columns 2. Multiply one or both equation by a number to obtain opposites for one variable 3. Add like terms to eleminate one variable. 4. Solve for remaining variable 5. Substitute into one of the original equations and solve for the other variable. Example; 4x-5y=-19 3x+7y=18 --﻿   -3[4x-5y=-19] 4[3x+7y=18] --   12x-15y=-57 __ 12x+28y=72  __ 43y=129 y= 3 --   4(x)-5(3) = -19 4x - 15= -19 4x= -4 x=-1 (-1,3)