Solve x^(2) + 7x + 6 = 0.

1) Factorise x2 + 7x +6 Numbers that multiply to make +6: 6 and 1, -6 and -1, 3 and 2, -3 and -2Which pair also add/subtract to make +7? 6 + 1 = 7 So factors are: (x+6)(x+1)2) Solve value of x.(x+6)(x+1)= 0. Therefore (x+6)=0 or (x+1)=0, So x= -6, x= -1 3) Check! Substitute x= -6 and x= -1 into x2 + 7x +6 = 0 For x= -6(-6)2 + 7(-6) + 6 = 0, 36 - 42 + 6 = 0, -6 + 6 = 0 (correct!) For x= -1 (-1)2 + 7(-1) +6 = 0, 1 - 7 + 6 = 0, -6 + 6 = 0 (correct!)4) Answers x= -1 x= -6

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