Solve the following equation by factorization (1)x^2-x-20=0 (2)x^2+11x-26=0 (3)(x+1)^2-6(x+1)+8=0
1. X ^ 2-x-20 = (x + 4) (X-5) x = - 4 or x = 5
2. X ^ 2 + 11x-26 = (x + 13) (X-2) x = - 13 or x = 2
3. Let (x + 1) = a
a^2-6a+8=(a-4)(a-2)
Replace a with the original
Original formula = (x-3) (x-1) x = 3 or x = 1
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