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2 years ago

Find the value of c that makes the expression a perfect square trinomial. x2 − 19x + c A) 361 B) 38 C) 361 2 D) 361 4

Mathematics

1 answer:

sasho [114]2 years ago

4 0

Answer:

A (361)

Step-by-step explanation:

A "perfect square trinomial" has the form

ax^2 + 2ab + b^2. If a happens to be 1, which it is in the given x^2 − 19x + c, then 2(1)(b) = - 19. Solving for b, we get b = -19/2.

Then b^2 in the general "perfect square trinomial" is the same as c: (-19/2)^2, or 90.25, or 90 1/4, or 361/4/

Choosing A (361) makes the given expression a perfect square trinomial.

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