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3 years ago

Please help!! I’m stuck on this

Mathematics

1 answer:

beks73 [17]3 years ago

7 0

Answer:

B. $x = -4\,\lor \,x = -1$

Step-by-step explanation:

Let $\sqrt{-4-5\cdot x} = x$ , we solve for $x$ by algebraic means.

1) $\sqrt{-4-5\cdot x} = x$ Given

2) $-4-5\cdot x = x^{2}$ Definition of power/Symmetry of equality

3) $x^{2}+5\cdot x + 4 = 0$ Compatibility with addition/Commutative and associative properties/Existence of additive inverse/Modulative property

4) $(x+4)\cdot (x+1) = 0$ $x^{2}+(a+b)\cdot x +a\cdot b = (x + a)\cdot (x+b)$

5) $x = -4\,\lor \,x = -1$ Result

Hence, the correct answer is B.

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Which is not a true statement about the transformation below

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Step-by-step explanation:

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3 years ago

Change the subject of the formula L = v 4kt - p to k.

Romashka [77]

Answer:

$\boxed{k = \frac{L^2 + p}{4t}}$

General Formulas and Concepts:

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Basic Equality Properties

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Step-by-step explanation:

Step 1: Define

Identify given.

$\displaystyle L = \sqrt{4kt - p}$

Step 2: Solve for k
We can use equality properties to help us rewrite the equation to get k as our subject:

Let's first square both sides:

$\displaystyle\begin{aligned}L = \sqrt{4kt - p} & \rightarrow L^2 = \big( \sqrt{4kt - p} \big) ^2 \\& \rightarrow L^2 = 4kt - p \\\end{aligned}$

Next, add p to both sides:

$\displaystyle\begin{aligned}L = \sqrt{4kt - p} & \rightarrow L^2 = \big( \sqrt{4kt - p} \big) ^2 \\& \rightarrow L^2 = 4kt - p \\& \rightarrow L^2 + p = 4kt \\\end{aligned}$

Next, divide 4t by both sides:

$\displaystyle\begin{aligned}L = \sqrt{4kt - p} & \rightarrow L^2 = \big( \sqrt{4kt - p} \big) ^2 \\& \rightarrow L^2 = 4kt - p \\& \rightarrow L^2 + p = 4kt \\& \rightarrow \frac{L^2 + p}{4t} = k \\\end{aligned}$

We can rewrite the new equation by swapping sides to obtain our final expression:

$\displaystyle\begin{aligned}L = \sqrt{4kt - p} & \rightarrow \boxed{k = \frac{L^2 + p}{4t}}\end{aligned}$

∴ we have changed the subject of the formula.

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Learn more about Algebra I: brainly.com/question/27698547

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Topic: Algebra I

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2 years ago

Sam is riding his bicycle. He rides for 11.2 kilometers at a speed of 7 kilometers per hour. For how many hours does he ride?

Airida [17]

Answer:

1.6 hours

Step-by-step explanation:

you divide 11.2 by 7

hope this is correct

6 0

3 years ago

Read 2 more answers

Use the formula P = 2 l + 2 w to find the length l of a rectangular lot if the width w is 40 feet and the perimeter P is 200 fee

jeyben [28]

Answer:

l = 60 feet

Step-by-step explanation:

use the equation and plug in the width(40 feet) for w and perimeter(200 feet) for p.

200 = 2l + 2(40)

then solve for l

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3 years ago

Wall posters are usually sold curled up in cylindrical cardboard tubes. if the length of the tube is 84.5 cm, and the diameter o

LekaFEV [45]

Length of the cylinder = 84.5 cm
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Answer: a. 637 cm²

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3 years ago