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3 years ago

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Mathematics

1 answer:

statuscvo [17]3 years ago

4 0

x = - 6 and x = 7

given x² - x - 42 = 0 ← quadratic in standard form

(x - 7 )(x + 6) = 0 ← in factored form

equate each factor to zero and solve for x

x - 7 = 0 ⇒ x = 7

x + 6 = 0 ⇒ x = - 6

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So, $\left[\begin{array}{cc}2&8\\-6&-9\end{array}\right]$ · X· $\left[\begin{array}{ccc}9&-3\\7&-6\end{array}\right]$ = $\left[\begin{array}{ccc}1&0\\0&1\end{array}\right]$

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