Question

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28. 6x² + 17x+ 12
30. 2x² + 11x - 21
32. 21x2 + 5 - 6
34. 3x² - 14x +8
36. V5 x² + 2x - 35
38. 7x² + 2/14x+2
40. 55x2 +20x +3.51
42. V2 x + 3x + 2
44, 15x² -r - 28
46. 2x² - 7x - 15
48. 6² - 117 - 35
50. 10x² - 9x-7
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Answer 1

Answer:

28.6x² + 17x+ 12

=>6x^2+9x+8x+12=0

=>3x(2x+3)+4(2x+3)=0

=>(3x+4)(2x+3)=0

=>3x+4=0 | 2x+3=0

=> 3x =(-4) | 2x=(-3)

=> x= (-4/3) | x=(-3/2)

30. 2x² + 11x - 21

=> 2x²+14x-3x-21=0

=> 2x(x+7)-3(x+7) =0

=> (2x-3)(x+7)=0

=>(2x-3)=0 | (x+7)=0

=>x = (3/2 ) | x =( -7)

32. 21 x² + 5 x - 6

=>21 x² + 5 x - 6=0

=>21 x² + 14x - 9x - 6=0

=> 7 ( 3 x + 2 ) - 3 ( 3 x + 2 )=0

=>( 3 x + 2 ) ( 7 x - 3 )=0

=>(3x+2)=0 | (7x-3)=0

=> 3x=(-2) | 7x=3

=> x=(-2/3)| x=7/3

34. 3x² - 14x +8

=>3x²-12x-2x+8=0

=>3x(x-4) -2(x-4)=0

=>(3x-2)(x-4)=0

=> 3x-2=0 | x-4=0

=> x= (2/3) | x=4

38.7x² + 2√14x + 2

=> 7x² + √14x + √14x + 2=0

=> √7x(√7x + √2) + √2(√7x + √2)=0

=> (√7x + √2)(√7x + √2)=0

=> √7x+ √2=0 | √7x+ √2=0

=> x=√2/√7