| Class VII |
Mathematics |
Ganita Prakash-II |
1 |
cm, and 80 cm, suppose the sidelengths had been 4 cm, 6 cm, 8 cm (this triangle can fit on our page). Is this information sufficient to replicate t... |
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| Class VII |
Mathematics |
Ganita Prakash-II |
1 |
there other ways of overlapping the vertices so that the triangles fit exactly over each other? The fact that these triangles are congruent shows t... |
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| Class VII |
Mathematics |
Ganita Prakash-II |
1 |
Prakash | Grade 7 | Part-II A A 80° A 80° 80° B 30° 70° B 30° 70° C B 30° 70° C C These triangles are seen to have the same shape, but not the same... |
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| Class VII |
Mathematics |
Ganita Prakash-II |
1 |
3: Draw a sufficiently long arc from Q of radius 4 cm cutting the line l. l S R 30° Q P 6 cm How do we find the required triangle from this figure?... |
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| Class VII |
Mathematics |
Ganita Prakash-II |
1 |
(as O is the midpoint of BC). Are there any other equal sides or angles? We also have, ∠AOB = ∠DOC, as they are vertically opposite angles. We see ... |
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| Class VII |
Mathematics |
Ganita Prakash-II |
1 |
4 cm Fig.1.2 How do we proceed with this problem? Here is a method. What are the measures of ∠B and ∠Y? We know that the sum of the angles of a tri... |
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| Class VII |
Mathematics |
Ganita Prakash-II |
1 |
the line l. Join PR. P Q 4 cm R ΔPQR is the required triangle. 16 Geometric Twins Consider the downward extension of line l below QR. Would the arc... |
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| Class VII |
Mathematics |
Ganita Prakash-II |
1 |
Thus, the triangles satisfy the RHS condition. Hence, Δ ADB ≅ ΔADC. Thisshowsthat∠B=∠C,astheyarecorrespondingpartsofcongruent triangles. Thus, the ... |
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| Class VII |
Mathematics |
Ganita Prakash-II |
1 |
= ED (c) AB = DF (d) ∠A = ∠D ∠B = ∠D = 90° ∠B = ∠E AC = FE AC = DF (e) AB = DF ∠B = ∠F AC = DE 3. It is given that OB = OC, and OA = OD. Show that ... |
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| Class VII |
Mathematics |
Ganita Prakash-II |
1 |
triangle are equal to the two sides and the included angle of another triangle, we say that the SAS (Side Angle Side) condition is satisfied. The S... |
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| Class VII |
Mathematics |
Ganita Prakash-II |
2 |
OPERATIONS WITH INTEGERS 2.1 A Quick Recap of Integers Rakesh’s Puzzle: A Number Game Rakesh gives you a challenge. “I have thought of two numbers”... |
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| Class VII |
Mathematics |
Ganita Prakash-II |
2 |
coin is struck to move it to the right. Each strike moves the coin a certain number of units of distance rightwards based on the force of the strik... |
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| Class VII |
Mathematics |
Ganita Prakash-II |
2 |
negative integers. First, let us model the line on which the coin moves as a number line. –ve +ve . .–5 –4 –3 –2 –1 0 1 2 3 4 5 6 . . . Let us cons... |
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| Class VII |
Mathematics |
Ganita Prakash-II |
2 |
to each other, and what are their directions? This Remember to start from 0. 1. b a –ve P 0 +ve 2. a b –ve 0 P +ve 3. a b –ve 0 +ve P 27 Ganita Pra... |
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| Class VII |
Mathematics |
Ganita Prakash-II |
2 |
represent addition and subtraction of integers. We now explore how to model multiplication of integers using tokens. Suppose we put some positive t... |
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| Class VII |
Mathematics |
Ganita Prakash-II |
2 |
need to do this 4 times. Remove 2greentokens fromthe zeropairs, 4times (– 4)=– 8 After removing the positives, 8 negatives are left in the bag. T... |
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| Class VII |
Mathematics |
Ganita Prakash-II |
2 |
0 × (–3) = 0 This is the inverse of the previous pattern. When the multiplicand is negative,foreveryunitdecreaseofthemultiplier,theproductincreases... |
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| Class VII |
Mathematics |
Ganita Prakash-II |
2 |
–3 = 21 8 × 3 = 24 –8 × 3 = –24 8 × –3 = –24 –8 × –3 = 24 9 × 3 = 27 –9 × 3 = –27 9 × –3 = –27 –9 × –3 = 27 10 × 3 = 30 –10 × 3 = –30 10 × –3 = –30... |
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| Class VII |
Mathematics |
Ganita Prakash-II |
2 |
same when we swap the multiplier and the multiplicand? Try this for some numbers. Observethefollowingpairsofmultiplications(fillintheblankswhere ne... |
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| Class VII |
Mathematics |
Ganita Prakash-II |
2 |
(18.30-32), Brahmagupta wrote: “The product or quotient of two fortunes is a fortune. The product or quotient of two debts is a fortune. The produc... |
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| Class VII |
Mathematics |
Ganita Prakash-II |
2 |
its position after 45 minutes? Solution: Solution to part (a) of the question: Method 1: We can model this using subtraction. The elevator moves at... |
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| Class VII |
Mathematics |
Ganita Prakash-II |
2 |
(– 46) ÷ (– 23) 2. A freezing process requires that the room temperature be lowered from 32°C at the rate of 5°C every hour. What will be the room ... |
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| Class VII |
Mathematics |
Ganita Prakash-II |
2 |
× b) × c. In the expression 5 × – 3 × 4, try to multiply 5 and 4 first and then multiply the product with – 3: (5 × 4) × – 3. 5 × 4 = 20, and 20 × ... |
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| Class VII |
Mathematics |
Ganita Prakash-II |
2 |
objects to visually understand why the distributive property holds. We can use the same setup even in the case of integers by using green tokens fo... |
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| Class VII |
Mathematics |
Ganita Prakash-II |
2 |
2. Find the values of the following expressions: (a) (– 27) ÷ 9 (b) 84 ÷ (– 4) (c) (– 56) ÷ (– 2) 3. Find the integer whose product with (– 1) is: ... |
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