A student performed the following system to find the solution to the equation x2-2x-8=0

Mathematics

2 answers:

Molodets [167]3 years ago

5 0

The student messed up on step one. The proper factoring is (x-4) (x+2)

Vsevolod [243]3 years ago

3 0

Answer:

B. in step 1

Step-by-step explanation:

Given that a student performed the following steps to find the solution of the quadratic equation $x^2-2x-8=0$ .

Step 1: Factor the polynomial into (x-4) and (x-2).

Step 2: x-4=0 and x-2=0

Step 3: x=4 and x=2.

Now we need to find about which step has the error.

let's multiply (x-4) and (x-2)

we get : $(x-4)(x-2)=x^2-4x-2x+8=x^2-8x+8$

While original problem has -8 as the last term. So that means factors are wrong.

Hence choice B. in step 1. is correct

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According to the recent poll, 22 1/4% of the people polled said that they approved of the city plan to expand the library. If 10

Sphinxa [80]

Answer:

Some 224 people were in favor of the expansion.

Step-by-step explanation:

Given that, according to the recent poll, 22 1/4% of the people polled said that they approved of the city plan to expand the library, if 1004 people was polled, to determine how many were in favor of the expansion should be done the following calculation:

1/4 = 0.25

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1004 x 22.25 / 100 = X

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Thus, some 224 people were in favor of the expansion.

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3 years ago

So far this year, the average monthly revenue at Lexington Times is 50,711. That is 5% less than the monthly average was last ye

SOVA2 [1]

53,380 was the average last year .

<u>Step-by-step explanation:</u>

Here we have , So far this year, the average monthly revenue at Lexington Times is 50,711. That is 5% less than the monthly average was last year. We need to find that What was the average last year . Let's find out:

Let the monthly average was last year be x , According to question the average monthly revenue at Lexington Times is 50,711 but , That is 5% less than the monthly average was last year . Following equation for above scenario is :

⇒ $x-\frac{5(x)}{100}=50711$