Question

Factor.
z squared+18z–19
(z - or + ?)(z- or + ?)

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Answer 1

(z - 1) (z + 19)

Explanation:

z² + 18z - 19

Consider the form x² + bx + c. Find a pair of integers whose product is c and whose sum is b. In this case, whose product is −19 and whose sum is 18.

-1, 19

Write the factored form using these integers.

(z - 1) (z + 19)