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Factor completely x2 + 20x − 36.

Group of answer choices
(x − 2)(x − 18)
(x + 2)(x − 18)
(x − 2)(x + 18)
Prime

User Arucker
by
5.6k points

1 Answer

3 votes

Answer:

Prime

Explanation:

x² + 20x − 36

You must find a pair of numbers that multiply to give -36 and add to give +20.

The likely candidates are 2 and 18, and they must have opposite signs to give a negative product.

+2 × (-18) = -36; +2 + (-18) = -16

-2 × 18 = -36; -2 + 8 = +16

Neither combination gives +20 as the sum.

The expression can't be factored with rational numbers.

The expression is prime.

User JOM
by
6.3k points