Weight Scales – Model A 19 B 12 C Find the Weight for each block. Cylinder = __7_ pounds Sphere = __8__ pounds Cube = __4__ pounds List of draw the steps you followed to find the weights of the blocks. 1. I see Scale B in Scale A 4+ -4 0 + 12 = 19 - 12 -12 0 7 2. Scale C 4. Check for accuracy + 2 = 12 -4 8 =8 =7 7+ -7 0 3. Scale B =8 =4 = 15 -7 8 A. 7+8 +4 =19 B. 4 + 8 = 12 C. 7 + 4 + 4 = 15 15 Shape Grids Columns 1 2 3 14 21 A 17 16 Step 1: Row 2 18 20 Step 3: row 1 5+ + + = 21 21 ÷ 3 = 7 =7 Step 2: Column 1 +7 + - 7 = 17 -7 10 + = 10 10 ÷ 2 = 5 =5 10 + -10 + 5 = 14 = 14 -10 4 =4 Step 4: Row 3 5 + 5 + A = 18 10 + A = 18 - 10 - 10 8 A=8 Step 5: Check for accuracy Columns 2 1 3 59 52 63 56 82 67 81 Step 1: I see row 3 within column 1 + + = 63, so 63 + - 63 Step 2: Row 3 19 + - 19 + + = 63 - 19 44 = 44 44 ÷ 2 = 22 = 22 = 82 - 63 19 Step 3: row 1 22 + 44 + - 44 + 22 = 59 = 59 - 44 15 = 15 Step 4: Check for accuracy. Patterns and Algebra- Shape Equations Solving algebraic expressions using pictures and models: Example 1: + + = 27 27 ÷ 3 = 9 9 + 9 + 9 = 27 =9 When the shapes are the same, the values for those shapes are the same. Example 2: A + B Step 1: A Step 2: B = 36 + 36 ÷ 3 = 12 Place a 12 in all 12 + + = 25 When doing EQUAtions, remember that what you do to one side, you have to do to the other. **you can’t put one shoe on without putting the other one** s = 25 25 – 12 = 13 = Step 3: Check for accuracy + 12 + 13 = 25 = 25 Example 3: A + B Step 1: A + = 48 + = 34 Substitute + with 34 + 34 = 48, so 48 – 34 = = 14 Step 2: A Place a 14 in all 14 + 14 + = 48 28 + = 48 s = 48 – 28 = 20 Step 3: B A 14 + 20 = 34 14 + 14 + 20 = 48 Place a 20 in all S Shape Equations: 2 Operations When you have an addition AND a subtraction open sentence: 1. Change the subtraction sentence to an addition sentence. 2. Substitute the new addition sentence into the other open sentence. Example: (5+ )+ (5 + A + B - )+ + = 31 = 31 =5+ + Step 1: B CHANGE - n = 5 to Step 2: Go back to A and SUBSTITUTE kh 5+ +5+ + = 31 10 + -10 + + + + 21 ÷ 3 = 7 , so Step 3: B =5+ =5+ = 31 -10 21 = 21 =7 Go back to A and B and place a 7 in all the - 7 = 5 + 7 +7 12, so for all = 12 Step 4: Go back to A and B to CHECK FOR ACCURACY. A 12 + 12 + 7 = 31 s to solve for s B 12 – 7 = 5 Shape Equations: 2 Operations- Explanation in Words When you have an addition and a subtraction open sentence: Step 1: CHANGE- you go to the subtraction problem and move the variable with the negative (–) symbol in front of it, to the other side of the equal sign. To do that, you perform it’s opposite operation to cancel it out on one side, and perform the same exact operation to the other side (remember you have to keep your equation balanced… “what you do to one side, you have to do to the other”). B - =5+ + =5+ Step 2: SUBSTITUTE your new addition open sentence into equation A. (5+ )+ (5 + A 5+ 10 + -10 + +5+ + + + + + 21 ÷ 3 = 7, so )+ + = 31 = 31 -10 21 = 21 = 31 = 31 Rewrite the equation so that there is one variable (square). 1. Combine numbers on the side of the = with the variables (5 + 5). 2. Once they are added together (10), move them to the other side of the equal sign. You have to cancel them out with the opposite operation (-10). 3. WHAT YOU DO TO ONE SIDE, YOU HAVE TO DO TO THE OTHER, so -10 from 31 and get 21. 4. Divide the new total into the number of like variables (3 squares). 21 ÷ 3 = 7. =7 Step 3: plug 7 in either equation and solve for the missing variable. I picked B. B - 7 = 5 + 7 +7 12, so = 12 You want to isolate the variable, so you perform the opposite operation of the -7 (+7), to move it from one side of the = to the other. Do the same to the other side and 5+7 = 12. Cell Sums A Step 1: WRITE 3 Equations: A + B = 17 A + C = 16 B + C = 15 17 16 B 15 C Step 2: COMPARE 2 Equations Box out 1st 2 problems with the variable A. 1. Cross out the As (they cancel each other out) A + B = 17 A + C+1 = 16 +1 2. I know that the 1st equation is 1 more, so _B= C + 1_ Step 3: SUBSTITUTE and REWRITE for equation with B and C as variables. Solve for C. B + C = 15 and B=C=1 (C + 1)+ C = 15 -1 -1 C + C = 14 14 ÷ 2= 7, so C = 7 Step 4: Solve for B. C= 7 B + C = 15 B + 7 = 15 -7 - 7 B=8 Step 5: Solve for A. B=8 OR A + B = 17 A + 8 = 17 A=9 Step 6: PROVE IT! A + B = 17 9 + 8 = 17 A + C = 16 9 + 7 = 16 B + C = 15 8 + 7 = 15 C=7 A + C = 16 A + 7 = 16 A=9 Weight Scales A 10 B 12 C 8 1. Find the Weight for each block. Cylinder = _____ pounds Sphere = _____ pounds Cube = _____ pounds 2. List of draw the steps you followed to find the weights of the blocks.