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56. An equation Is shown.

x? + 8x + 19 = 0
Part A: What is an equivalent equation that results from completing the square?

User Enoktate
by
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1 Answer

1 vote

Answer:

(x + 4)^2 + 3 = 0

Explanation:

When you multiply out (a + b)^2, you get a^2 + 2ab + b^2. We already know the a^2 term, which is x^2. We can deduct the first term of the square is x because x * x is x^2, and x would correspond with a. Next, we can connect the 2ab term with 8x, as it includes the variable x.

2ab = 8x

We have established a = x, so:

2xb = 8x

b = 4

We can put this together to get the square:

(x^2 + 8x + 16) + 3 = 0

(the three is added to get a last term of 19 in the given equation)

When we factor the square, it turns out as:

(x + 4)^2 + 3 = 0

Note: Sorry if the answer was a bit confusing, this is kinda hard to explain.

User JeffP
by
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