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spin [16.1K]
3 years ago
13

Solve x2-14x+21=0 by completing the square

Mathematics
1 answer:
ankoles [38]3 years ago
4 0
x^2-14x+21=0\\\\x^2-2x\cdot7+7^2-7^2+21=0\\\\(x-7)^2-49+21=0\\\\(x-7)^2-28=0\\\\(x-7)^2=28\iff x-7=-\sqrt{28}\ \vee\ x-7=\sqrt{28}\\\\x=7-\sqrt{4\cdot7}\ \vee\ x=7+\sqrt{4\cdot7}\\\\x=7-2\sqrt7\ \vee\ x=7+2\sqrt7
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What is 2 x 10 to the -6th power?
White raven [17]

Answer:

2 x 10 to the -6th power is .000002.

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3 years ago
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A tourist ignores the warning signs and leaves food in his car while he goes for a hike. A mama bear and her cub open the car do
alukav5142 [94]

Answer:

0 sec. I help him get the tourist too :)

Step-by-step explanation:

jk, but her cub takes 13 and the mama 4

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Suppose that the proportions of blood phenotypes in a particular population are as follows: A B AB O 0.48 0.13 0.03 0.36 Assumin
Serggg [28]

Answer:

P(O and O) =0.1296

P=0.3778

Step-by-step explanation:

Given that

blood phenotypes in a particular population

A=0.48

B=0.13

AB=0.03

O=0.36

As we know that when A and B both are independent that

P(A and B)= P(A) X P(B)

The probability that both phenotypes O are in independent:

P(O and O)= P(O) X P(O)

P(O and O)= 0.36 X 0.36 =0.1296

P(O and O) =0.1296

The probability that the phenotypes of two randomly selected individuals match:

Here  four case are possible

So

P=P(A and A)+P(B and B)+P(AB and AB)+P(O and O)

P=0.48 x 0.48 + 0.13 x 0.13 + 0.03 x 0.03 + 0.36 x 0.36

P=0.3778

7 0
3 years ago
Can someone please help me on this question <br> I will give brainliest
xz_007 [3.2K]

Answer:

A) 3 in

General Formulas and Concepts:

<u>Pre-Algebra</u>

Order of Operations: BPEMDAS

  1. Brackets
  2. Parenthesis
  3. Exponents
  4. Multiplication
  5. Division
  6. Addition
  7. Subtraction
  • Left to Right

Equality Properties

<u>Geometry</u>

  • Surface Area of a Sphere: SA = 4πr²
  • Diameter: d = 2r

Step-by-step explanation:

<u>Step 1: Define</u>

SA = 23 in²

<u>Step 2: Find </u><em><u>r</u></em>

  1. Substitute [SAS]:                    23 in² = 4πr²
  2. Isolate <em>r </em>term:                         23 in²/(4π) = r²
  3. Isolate <em>r</em>:                                  √[23 in²/(4π)] = r
  4. Rewrite:                                   r = √[23 in²/(4π)]
  5. Evaluate:                                 r = 1.35288 in

<u>Step 3: Find </u><em><u>d</u></em>

  1. Substitute [D]:                    d = 2(1.35288 in)
  2. Multiply:                              d = 2.70576 in
  3. Round:                                d ≈ 3 in
4 0
3 years ago
A grasshopper covered a distance of 5 yards in 9 equal hops.How many yards did the grasshopper travel on each hop?
Luda [366]
5/9 = .55555555555 yards traveled per hop
15/9 = 1.6666667 feet per hop
5 0
3 years ago
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