Write down the quadratic equation whose roots are x = 1 and x = -7 and the coefficient of is 1.
X = 1 means that one of the factors is (X – 1) and
X = –7 means that the other factor is (X + 7)
Multiply them together (X – 1)(X + 7) and the equations is X2 + 6X – 7 = 0
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