Starting from (-1) x5, write various products showing some patterns to show (-1) x (-1) = 1.

(-1)x5 = -5 (-1)x4 = -4
(-1)x3 = -3 (-1)x2 = -2
(-1)x1 = -1 (-1)x0 = 0
(-1)x(-1)=1

Class 7 Maths Exercise 1.3 Questions 4, 5

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