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3 years ago

12

Solve the quadratic equation: x^2+ 2x + 7 = 21

1 answer:

Crank3 years ago

3 0

Answer:

x1 = -4.872983346

x2 = 2.872983346

Step-by-step explanation:

<u>Given:</u>

x^2+2x+7=21

<u>Subtract 21 on both sides to get the right side equal to 0:</u>

x^2+2x-14=0

<u>Use the quadratic formula:</u>

x1 = -4.872983346

x2 = 2.872983346

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Line GJ is tangent to point A at point G.<br><br> If AG = 9 and GJ = 12, find AJ.

kompoz [17]

GJ is a tangent
АG is a radius
A tangent line to a circle is perpendicular to the radius drawn to the tangent point ⇒ m∠АGJ = 90° ⇒ ΔАGJ is the right triangle.

<span>By the Pythagorean theorem:
</span>AJ² = АG² + GJ²
AJ² = 9² + 12² = 81 + 144 = 225
AJ = √225 = 15 units.

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3 years ago

Read 2 more answers

That's the question ??

Oksanka [162]

Step-by-step explanation:

Before we answer, the area of a Circle given it radius is

$a = \pi r {}^{2}$

The area of a circle given it diameter is

$a = \pi( \frac{d}{2} ) {}^{2}$

So let answers question 1-4.

1. The area is

$1024\pi$

2. The area is

$576\pi$

3.

$1.225\pi$

4.

$309.76\pi$

For the 5th problem, circumference is

$\pi \times d$

where d is the diameter and

$2\pi r$

where r is the radius.

A circumference of 100 m means the radius is 50 because

$2\pi \times r = 100\pi$

$r = 50$

So this means the area is

$2500 {\pi}$

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3 years ago

Hey bag contains blue marbles and red marbles 17 in tomorrow the number to blue marbles seven less than two times a number of re

nikitadnepr [17]

There are 20 blue marbles in the bag.

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3 years ago

What is the area of the unshaded region

QveST [7]

Need more info please ?

8 0

3 years ago

Please answer this with explanation. Please I really am struggling. I will mark you brainalist. Please solve it Please

Hatshy [7]

Answer:

13, 11, 4, 16, 6, 22

Step-by-step explanation:

<em>Let the second digit be x and the last digit be y</em>

Given:

Data set: 13, x, 4, 16, 6, y
Mean = 12
y = 2x or x = 2y

The mean of the data is the average. The average can be calculated by determining the sum of the terms and dividing it by the total digits.

$\implies \text{Mean of data:} \ \dfrac{13 + x + 4 + 16 + 6 + y}{6} = 12$

Let us substitute the value of y (2x) in the data.

$\implies \dfrac{13 + x + 4 + 16 + 6 + 2x}{6} = 12$

Now, add all the terms in the data and simplify.

$\implies \dfrac{39 + x +2x}{6} = 12$

$\implies \dfrac{39 + 3x}{6} = 12$

Distribute the denominators and simplify.

$\implies \dfrac{39}{6} + \dfrac{3x}{6} = 12$

$\implies \dfrac{13}{2} + \dfrac{x}{2} = 12$

$\implies 6.5 + \dfrac{x}{2} = 12$

Subtract 6.5 both sides and simplify.

$\implies 6.5 + \dfrac{x}{2} - 6.5 = 12 - 6.5$

$\implies \dfrac{x}{2} = 5.5$

Use cross multiplication and simplify.

$\implies x= 5.5 \times 2$

$\implies x= 11$

To determine the value of "y", simply substitute the value of "x" into the expression that represents the value of "y".

$\implies y = 2x$

$\implies y = 2(11)$

$\implies y = 22$

When the x and y values are substituted in the data, we get;

⇒ 13, 11, 4, 16, 6, 22

Therefore, the data is 13, 11, 4, 16, 6, 22.

8 0

2 years ago