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I. Before you watch the video answer the following questions. The title of the video is "Algebra I" What do you think this video will be about? I think that the video will be about definition and description of “Algebra I” and the themes studied in that course and its object. Mention five words you think you might listen to in the video. · Mathematic · Course · Study · Objectives · Sets · Rules · Arithmetic
 * Good Job 5pts [[image:xmas_tree2.gif]] **
 * Video 3: "Algebra I" **

II. Now click on the following link and watch the video. While watching, please answer the following questions: []

Image taken from: [|http://www.ehow.com/how_2363893_solve-algebraic-equations.html on August 12th. 2009] 1. Mr. Mc Call is solving three types of equations in this video. Which are those types of equations? · With one variable · Whit variables on both sides · Formulas 2. What are the two keys he mentions for solving any equation? · Additive inverse or opposite · Reciprocal 3. a. Mention the steps he takes to solve the 1st problem. The equation is the following: 14=-2-(x/5) · He adds the inverse of -2 on both sides of equation: 14 +2=-2 +2 -(x/5), where -2 +2 =0….. then 16 =0 -(x/5) and 16=x/5 · He separates the expression on right side: -(x/5)=-(1/5)*x, (‘*’ is the multiplication’s symbol) · He multiplies by the reciprocal of -1/5 on both sides of equation: 16*(-5/1)=(-1/5)*(-5/1)*x, where (-1/5)*(-5/1) and (-5/1)=-5, then 16*(-5)=1*x · He calculates: -80=x b. What kind of equation is this one? The equation solved on the first problem is an equation with “//one variable”// on a side and a fraction. 4. a. Mention the steps he takes to solve the 2nd problem. The equation is the following: 6x -2 +3x=4*(x -5). ·<span style="font-family: "Times New Roman"; font-size-adjust: none; font-size: 7pt; font-stretch: normal; font-style: normal; font-variant: normal; font-weight: normal; line-height: normal;"> He use <span style="color: #ff0000; font-family: Arial,Helvetica,sans-serif; font-size: 8pt; line-height: 115%;">**s** the distributive property (a*(a +b) =a*b +a*c): 4*(x -5) =4*x –(4*5) =4x -20. Then 6x -2 +3x=4x -20. ·<span style="font-family: "Times New Roman"; font-size-adjust: none; font-size: 7pt; font-stretch: normal; font-style: normal; font-variant: normal; font-weight: normal; line-height: normal;"> He calculates on left side: 6x -2 +3x= 9x -2. Then 9x -2 =4x -20. ·<span style="font-family: "Times New Roman"; font-size-adjust: none; font-size: 7pt; font-stretch: normal; font-style: normal; font-variant: normal; font-weight: normal; line-height: normal;"> He adds the inverse of 4x on both sides of equation: 9x -4x -2 =4x -4x -20, where 9x -4x= 5x and 4x -4x =0, then 5x -2 =-20. ·<span style="font-family: "Times New Roman"; font-size-adjust: none; font-size: 7pt; font-stretch: normal; font-style: normal; font-variant: normal; font-weight: normal; line-height: normal;"> He adds the inverse of -2 on both sides of equation: 5x -2 +2 =-20 +2, where -2 +2=0 and -20 +2 =-18, then 5x =-18. ·<span style="font-family: "Times New Roman"; font-size-adjust: none; font-size: 7pt; font-stretch: normal; font-style: normal; font-variant: normal; font-weight: normal; line-height: normal;"> He multiplies by the reciprocal of 5 on both sides of equation: 5x*(1/5) = 18*(1/5), where 5x*(1/5) = 5x/5 and 5/5 =1, then 1x =x =18/5.

b. What kind of equation is this one? The equation solved on the second problem is an equation with “//variables on both sides”//. 5. a. Mention the steps he takes to solve the 3rd problem. The objective is solving this equation for w. The equation is: P= 2L +2W ·<span style="font-family: "Times New Roman"; font-size-adjust: none; font-size: 7pt; font-stretch: normal; font-style: normal; font-variant: normal; font-weight: normal; line-height: normal;"> He adds the inverse of 2L on both sides of equation: P -2L= 2L -2L +2W, where 2L -2L =0, then P -2L =0 +2W = 2W. ·<span style="font-family: "Times New Roman"; font-size-adjust: none; font-size: 7pt; font-stretch: normal; font-style: normal; font-variant: normal; font-weight: normal; line-height: normal;"> He multiplies by the reciprocal of 2 on both sides of equation: (P -2L)*(1/2) = 2W*(1/2), by distributive property (P -2L)*1/2 =(P/2) –(2L/2). 2*1/2 = 1, then (P/2) –1L = 1W and (P/2) –L = W. b. What kind of equation is this one? The equation solved on the third problem is a formula, an equation with “//multiple variables”//. 6. a. Mention the steps he takes to solve the 4th problem. The objective is solving this equation for b. The equation is: a =(b-c)/d ·<span style="font-family: "Times New Roman"; font-size-adjust: none; font-size: 7pt; font-stretch: normal; font-style: normal; font-variant: normal; font-weight: normal; line-height: normal;"> He multiplies by the reciprocal of 1/d on both sides of equation: a*d =(b -c)*d/d, where d/d=1, then a*d =b -c. ·<span style="font-family: "Times New Roman"; font-size-adjust: none; font-size: 7pt; font-stretch: normal; font-style: normal; font-variant: normal; font-weight: normal; line-height: normal;"> He adds the inverse of –c on both sides of equation: (a*d) +c =b –c +c, where –c +c =0, then (a*d) +c =b b. What kind of equation is this one? The equation solved on the fourth problem is a formula, an equation with “//multiple variables”//. c. What’s the difference between problem 3 and problem 4? The difference between problem 3 and problem 4 is than in the problem 4 the right side of equation, where the unknown quantity (“b”) is is divide by “d”. 7. Did you like the video? Yes I liked the video. 8. What new things did you learn? I learn <span style="color: #ff0000; font-family: Arial,Helvetica,sans-serif; font-size: 8pt; line-height: 115%;">ED that the word inverse have a false cognate to Spanish on mathematic. Because on Math the Spanish meaning of //“inverso”// is the same to the English //“reciprocal”.//