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Page 2 Factorise: x 2 + 14x + 49 S o l u t i o n : We have: x 2 +14x +49 = x 2 +2 ×x ×7 +(7) 2 = (x +7) 2 ? x 2 +14x +49 = (x +7) 2 Q u e s t i o n : 5 9 Factorise: 1 + 2x + x 2 S o l u t i o n : We have: 1 +2x +x 2 = x 2 +2x +1 = x 2 +2 ×x ×1 +(1) 2 = (x +1) 2 ? 1 +2x +x 2 = (x +1) 2 Q u e s t i o n : 6 0 Factorise: 9 + 6z + z 2 S o l u t i o n : We have; 9 +6z +z 2 = z 2 +6z +9 = z 2 +2 ×x ×3 +(3) 2 = (z +3) 2 ? 9 +6z +z 2 = (z +3) 2 Q u e s t i o n : 6 1 Factorise: x 2 + 6ax + 9a 2 S o l u t i o n : We have: x 2 +6ax +9a 2 = x 2 +2 ×x ×3a +(3a) 2 = (x +3a) 2 ? x 2 +6ax +9a 2 = (x +3a) 2 Q u e s t i o n : 6 2 Factorise: 4y 2 + 20y + 25 S o l u t i o n : We have: 4y 2 +20y +25 = (2y) 2 +2 ×2y ×5 +(5) 2 = (2y +5) 2 ? 4y 2 +20y +25 = (2y +5) 2 Q u e s t i o n : 6 3 Factorise: 36a 2 + 36a + 9 S o l u t i o n : We have: 36a 2 +36a +9 = (6a) 2 +2 ×6a ×3 +(3) 2 = (6a +3) 2 ? 36a 2 +36a +9 = (6a +3) 2 Q u e s t i o n : 6 4 Factorise: 9m 2 + 24m + 16 S o l u t i o n : We have: 9m 2 +24m +16 = (3m) 2 +2 ×3m ×4 +(4) 2 = (3m +4) 2 ? 9m 2 +24m +16 = (3m +4) 2 Q u e s t i o n : 6 5 Factorise: z 2 + z + 1 4 S o l u t i o n : We have: z 2 +z + 1 4 = z 2 +2 ×z × 1 2 × 1 2 2 = z + 1 2 2 ? z 2 +z + 1 4 = z + 1 2 2 Q u e s t i o n : 6 6 Factorise: 49a 2 + 84ab + 36b 2 S o l u t i o n : We have: ( ) ( ) ( ) Page 3 Factorise: x 2 + 14x + 49 S o l u t i o n : We have: x 2 +14x +49 = x 2 +2 ×x ×7 +(7) 2 = (x +7) 2 ? x 2 +14x +49 = (x +7) 2 Q u e s t i o n : 5 9 Factorise: 1 + 2x + x 2 S o l u t i o n : We have: 1 +2x +x 2 = x 2 +2x +1 = x 2 +2 ×x ×1 +(1) 2 = (x +1) 2 ? 1 +2x +x 2 = (x +1) 2 Q u e s t i o n : 6 0 Factorise: 9 + 6z + z 2 S o l u t i o n : We have; 9 +6z +z 2 = z 2 +6z +9 = z 2 +2 ×x ×3 +(3) 2 = (z +3) 2 ? 9 +6z +z 2 = (z +3) 2 Q u e s t i o n : 6 1 Factorise: x 2 + 6ax + 9a 2 S o l u t i o n : We have: x 2 +6ax +9a 2 = x 2 +2 ×x ×3a +(3a) 2 = (x +3a) 2 ? x 2 +6ax +9a 2 = (x +3a) 2 Q u e s t i o n : 6 2 Factorise: 4y 2 + 20y + 25 S o l u t i o n : We have: 4y 2 +20y +25 = (2y) 2 +2 ×2y ×5 +(5) 2 = (2y +5) 2 ? 4y 2 +20y +25 = (2y +5) 2 Q u e s t i o n : 6 3 Factorise: 36a 2 + 36a + 9 S o l u t i o n : We have: 36a 2 +36a +9 = (6a) 2 +2 ×6a ×3 +(3) 2 = (6a +3) 2 ? 36a 2 +36a +9 = (6a +3) 2 Q u e s t i o n : 6 4 Factorise: 9m 2 + 24m + 16 S o l u t i o n : We have: 9m 2 +24m +16 = (3m) 2 +2 ×3m ×4 +(4) 2 = (3m +4) 2 ? 9m 2 +24m +16 = (3m +4) 2 Q u e s t i o n : 6 5 Factorise: z 2 + z + 1 4 S o l u t i o n : We have: z 2 +z + 1 4 = z 2 +2 ×z × 1 2 × 1 2 2 = z + 1 2 2 ? z 2 +z + 1 4 = z + 1 2 2 Q u e s t i o n : 6 6 Factorise: 49a 2 + 84ab + 36b 2 S o l u t i o n : We have: ( ) ( ) ( ) 49a 2 +84ab +36b 2 = (7a) 2 +2 ×7a ×6b +(6b) 2 = (7a +6b) 2 ? 49a 2 +84ab +36b 2 = (7a +6b) 2 Q u e s t i o n : 6 7 Factorise: p 2 - 10p + 25 S o l u t i o n : We have: p 2 -10p +25 = p 2 -2 ×p ×5 +(5) 2 = (p -5) 2 ? p 2 -10p +25 = (p -5) 2 Q u e s t i o n : 6 8 Factorise: 121a 2 - 88ab + 16b 2 S o l u t i o n : We have: 121a 2 -88ab +16b 2 = (11a) 2 -2 ×11a ×4b +(4b) 2 = (11a -4b) 2 ? 121a 2 -88ab +16b 2 = (11a -4b) 2 Q u e s t i o n : 6 9 Factorise: 1 - 6x + 9x 2 S o l u t i o n : We have: 1 -6x +9x 2 = 9x 2 -6x +1 = (3x) 2 -2 ×3x ×1 +(1) 2 = (3x -1) 2 ? 1 -6x +9x 2 = (3x -1) 2 Q u e s t i o n : 7 0 Factorise: 9y 2 - 12y + 4 S o l u t i o n : We have: 9y 2 -12y +4 = (3y) 2 -2 ×3y ×2 +(2) 2 = (3y -2) 2 ? 9y 2 -12y +4 = (3y -2) 2 Q u e s t i o n : 7 1 Factorise: 16x 2 - 24x + 9 S o l u t i o n : We have: 16x 2 -24x +9 = (4x) 2 -2 ×4x ×3 +(3) 2 = (4x -3) 2 ? 16x 2 -24x +9 = (4x -3) 2 Q u e s t i o n : 7 2 Factorise: m 2 - 4mn + 4n 2 S o l u t i o n : We have: m 2 -4mn +4n 2 = m 2 -2 ×m ×2n +(2n) 2 = (m -2n) 2 ? m 2 -4mn +4n 2 = (m -2n) 2 Q u e s t i o n : 7 3 Factorise: a 2 b 2 - 6abc + 9c 2 S o l u t i o n : We have: a 2 b 2 -6abc +9c 2 = (ab) 2 -2 ×ab ×3c +(3c) 2 = (ab -3c) 2 Q u e s t i o n : 7 4 Factorise: m 4 + 2m 2 n 2 + n 4 S o l u t i o n : We have: m 4 +2m 2 n 2 +n 4 = m 2 2 +2 ×m 2 ×n 2 + n 2 2 = m 2 +n 2 2 ? m 4 +2m 2 n 2 +n 4 = m 2 +n 2 2 ( ) ( ) ( ) ( ) Page 4 Factorise: x 2 + 14x + 49 S o l u t i o n : We have: x 2 +14x +49 = x 2 +2 ×x ×7 +(7) 2 = (x +7) 2 ? x 2 +14x +49 = (x +7) 2 Q u e s t i o n : 5 9 Factorise: 1 + 2x + x 2 S o l u t i o n : We have: 1 +2x +x 2 = x 2 +2x +1 = x 2 +2 ×x ×1 +(1) 2 = (x +1) 2 ? 1 +2x +x 2 = (x +1) 2 Q u e s t i o n : 6 0 Factorise: 9 + 6z + z 2 S o l u t i o n : We have; 9 +6z +z 2 = z 2 +6z +9 = z 2 +2 ×x ×3 +(3) 2 = (z +3) 2 ? 9 +6z +z 2 = (z +3) 2 Q u e s t i o n : 6 1 Factorise: x 2 + 6ax + 9a 2 S o l u t i o n : We have: x 2 +6ax +9a 2 = x 2 +2 ×x ×3a +(3a) 2 = (x +3a) 2 ? x 2 +6ax +9a 2 = (x +3a) 2 Q u e s t i o n : 6 2 Factorise: 4y 2 + 20y + 25 S o l u t i o n : We have: 4y 2 +20y +25 = (2y) 2 +2 ×2y ×5 +(5) 2 = (2y +5) 2 ? 4y 2 +20y +25 = (2y +5) 2 Q u e s t i o n : 6 3 Factorise: 36a 2 + 36a + 9 S o l u t i o n : We have: 36a 2 +36a +9 = (6a) 2 +2 ×6a ×3 +(3) 2 = (6a +3) 2 ? 36a 2 +36a +9 = (6a +3) 2 Q u e s t i o n : 6 4 Factorise: 9m 2 + 24m + 16 S o l u t i o n : We have: 9m 2 +24m +16 = (3m) 2 +2 ×3m ×4 +(4) 2 = (3m +4) 2 ? 9m 2 +24m +16 = (3m +4) 2 Q u e s t i o n : 6 5 Factorise: z 2 + z + 1 4 S o l u t i o n : We have: z 2 +z + 1 4 = z 2 +2 ×z × 1 2 × 1 2 2 = z + 1 2 2 ? z 2 +z + 1 4 = z + 1 2 2 Q u e s t i o n : 6 6 Factorise: 49a 2 + 84ab + 36b 2 S o l u t i o n : We have: ( ) ( ) ( ) 49a 2 +84ab +36b 2 = (7a) 2 +2 ×7a ×6b +(6b) 2 = (7a +6b) 2 ? 49a 2 +84ab +36b 2 = (7a +6b) 2 Q u e s t i o n : 6 7 Factorise: p 2 - 10p + 25 S o l u t i o n : We have: p 2 -10p +25 = p 2 -2 ×p ×5 +(5) 2 = (p -5) 2 ? p 2 -10p +25 = (p -5) 2 Q u e s t i o n : 6 8 Factorise: 121a 2 - 88ab + 16b 2 S o l u t i o n : We have: 121a 2 -88ab +16b 2 = (11a) 2 -2 ×11a ×4b +(4b) 2 = (11a -4b) 2 ? 121a 2 -88ab +16b 2 = (11a -4b) 2 Q u e s t i o n : 6 9 Factorise: 1 - 6x + 9x 2 S o l u t i o n : We have: 1 -6x +9x 2 = 9x 2 -6x +1 = (3x) 2 -2 ×3x ×1 +(1) 2 = (3x -1) 2 ? 1 -6x +9x 2 = (3x -1) 2 Q u e s t i o n : 7 0 Factorise: 9y 2 - 12y + 4 S o l u t i o n : We have: 9y 2 -12y +4 = (3y) 2 -2 ×3y ×2 +(2) 2 = (3y -2) 2 ? 9y 2 -12y +4 = (3y -2) 2 Q u e s t i o n : 7 1 Factorise: 16x 2 - 24x + 9 S o l u t i o n : We have: 16x 2 -24x +9 = (4x) 2 -2 ×4x ×3 +(3) 2 = (4x -3) 2 ? 16x 2 -24x +9 = (4x -3) 2 Q u e s t i o n : 7 2 Factorise: m 2 - 4mn + 4n 2 S o l u t i o n : We have: m 2 -4mn +4n 2 = m 2 -2 ×m ×2n +(2n) 2 = (m -2n) 2 ? m 2 -4mn +4n 2 = (m -2n) 2 Q u e s t i o n : 7 3 Factorise: a 2 b 2 - 6abc + 9c 2 S o l u t i o n : We have: a 2 b 2 -6abc +9c 2 = (ab) 2 -2 ×ab ×3c +(3c) 2 = (ab -3c) 2 Q u e s t i o n : 7 4 Factorise: m 4 + 2m 2 n 2 + n 4 S o l u t i o n : We have: m 4 +2m 2 n 2 +n 4 = m 2 2 +2 ×m 2 ×n 2 + n 2 2 = m 2 +n 2 2 ? m 4 +2m 2 n 2 +n 4 = m 2 +n 2 2 ( ) ( ) ( ) ( ) Q u e s t i o n : 7 5 Factorise: (l + m) 2 - 4lm S o l u t i o n : We have: (l +m) 2 -4lm = l 2 +m 2 +2lm -4lm = l 2 +m 2 +2lm -4lm = l 2 +m 2 -2lm = (l) 2 +(m) 2 -2 ×l ×m = (l -m) 2 ? (l +m) 2 -4lm = (l -m) 2 Q u e s t i o n : 7 6 Factorise: x 2 + 5x + 6 S o l u t i o n : The given expression is x 2 + 5x + 6. Find two numbers that follow the conditions given below: Sum = 5 Product = 6Clearly, the numbers are 3 and 2. x 2 + 5x + 6 = x 2 + 3x + 2x + 6 Q u e s t i o n : 7 7 Factorise: y 2 + 10y + 24 S o l u t i o n : The given expression is y 2 + 10y + 24. Find two numbers that follow the conditions given below: Sum = 10 Product = 24Clearly, the numbers are 6 and 4. y 2 + 10y + 24 = y 2 + 6y + 4y Q u e s t i o n : 7 8 Factorise: z 2 + 12z + 27 S o l u t i o n : The given expression is z 2 + 12z + 27. Find two numbers that follow the conditions given below: Sum = 12 Product = 27Clearly, the numbers are 9 and 3. z 2 + 12z + 27 = z 2 + 9z + 3z Q u e s t i o n : 7 9 Factorise: p 2 + 6p + 8 S o l u t i o n : The given expression is p 2 + 6p + 8. Find two numbers that follow the conditions given below: Sum = 6 Product = 8Clearly, the numbers are 4 and 2. p 2 + 6p + 8 = p 2 + 4p + 2p +8 Q u e s t i o n : 8 0 Factorise: x 2 + 15x + 56 S o l u t i o n : The given expression is x 2 + 15x + 56. Find two numbers that follow the conditions given below: Sum = 15 Product = 56Clearly, the numbers are 8 and 7. x 2 + 15x + 56 = x 2 + 8x + 7x Q u e s t i o n : 8 1 Factorise: y 2 + 19y + 60 S o l u t i o n : The given expression is y 2 + 19y + 60. Find two numbers that follow the conditions given below: Sum = 19 Product = 60Clearly, the numbers are 15 and 4. y 2 + 19y + 60 = y 2 + 15y + 4 Q u e s t i o n : 8 2 Factorise: x 2 + 13x + 40 S o l u t i o n : The given expression is x 2 + 13x + 40. Find two numbers that follow the conditions given below: Sum = 13 Product = 40Clearly, the numbers are 8 and 5. x 2 + 13x + 40 = x 2 + 8x + 5x Q u e s t i o n : 8 3 Factorise: q 2 - 10q + 21 S o l u t i o n : The given expression is q 2 -10q + 21. Find two numbers that follow the conditions given below: Sum = -10 Product = 21Clearly, the numbers are -7 and -3. q 2 -10q + 21 = q 2 -7q -3q + Q u e s t i o n : 8 4 Factorise: p 2 + 6p - 16 S o l u t i o n : The given expression is p 2 + 6p -16. Find two numbers that follow the conditions given below: Sum = 6 Product = -16Clearly, the numbers are 8 and -2. p 2 + 6p -16 = p 2 +8p -2p -16 Q u e s t i o n : 8 5 Factorise: x 2 - 10x + 24 S o l u t i o n : The given expression is x 2 -10x +24. Find two numbers that follow the conditions given below: Sum = -10 Product = 24Clearly, the numbers are -6 and -4. x 2 -10x +24 = x 2 -6x -4x +24 ( )Read More
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