Difference of squares 9x^2-4

In the figure below, the segment that appears to be tangent to the circle is tangent to the circle. Which of the following is th

maria [59]

Answer:

Step-by-step explanation:

Check attachment for diagram,

Since line AB is tangent to the circle then, <OAB is a right angle,

Then, we can apply Pythagoras theorem to the right angle triangle,

NOTE: from the centre of the circle to the tangent point at A is the radius of the circle,

And also, the total length of OB is

OB = r + 15

Then, applying Pythagorean theorem

OB² = OA² + AB²

(r+15)² = r² + 25²

(r+15)(r+15) = r² + 625

r² + 15r + 15r + 225 = r² + 625

Collect like terms

r² + 30r - r² = 625 - 225

30r = 400

Divide both sides by 30

r = 400 / 30

r = 13.33

So, the diameter of the circle is related to the radius by the relation

Diameter = 2 × radius

d = 2 × r

d = 2 × 13.33

d = 26.67

To the nearest tenth implies that to 1d•p

d ≈ 26.7

So, the diameter of the circle is 26.7

6 0

3 years ago

BRAINLIEST!!!!

Len [333]

Answer:

The answer is option 3.

Step-by-step explanation:

Option 3 is correct because it has parentheses around 40 - x, but not the cube itself or the 3rd power if you didn't know what I meant. Anyway, the reason this is correct is because if you look at any order of operations, you will notice that parentheses always comes before powered numbers, so if you were to choose, say option 2, it would be a completely different answer than option 3, not to mention wrong also.

8 0

3 years ago

The length of the base and the height of a triangle are numerically equal. Their sum is 6 less than the number of units in the a

Troyanec [42]

Base = Height, Let them be x.

$( x \times x) \div 2 = (x + x) + 6 \\ x ^{2} \div 2 = 2x + 6 \\ \frac{1}{2} x^{2} - 2x - 6 = 0$
Solve quadratic equation:
x=6, x=-2(rejected because base and height is positive)

6x6/2 =18

6 0

3 years ago

Canceling units is also called: a. changing the value c. multiplication b. unit analysis d. making connections

SOVA2 [1]

Canceling units is also called unit analysis.

This is also called dimensional analysis.

What is a unit of analysis in statistics?

The unit of analysis is the entity that you're analyzing. It's called this because it's your analysis (what you want to examine) that determines what this unit is, rather than the data itself.
Because it is the analysis you do in your study that determines what the unit is.
For instance, if you are comparing the children in two classrooms on achievement test scores, the unit is the individual child because you have a score for each child.

For example -

1 ft = 12 in

3 ft = $3 ft * \frac{12 in }{1 ft}$

3 ft = ( 3 * 12 ) in ⇒ 36 in

Learn more about unit analysis

brainly.com/question/15579410

#SPJ4

3 0

2 years ago

4) The path of a satellite orbiting the earth causes it to pass directly over two

Naily [24]

Answers:

Satellite is approximately 2446.43 km from station A.
Satellite is approximately 2441.61 km above the ground.

=========================================================

Explanation:

I'm assuming tracking stations A and B are at the same elevation and are on flat ground. In reality, this is likely not the case; however, for the sake of simplicity, we'll assume this is the case.

The diagram is shown below. Points A and B describe the two stations, while point C is the satellite's location. Point D is on the ground directly below the satellite. We have these lengths

AB = 60 km
AD = x
CD = h

Focusing on triangle ACD, we can apply the tangent rule to isolate h.

tan(angle) = opposite/adjacent

tan(A) = CD/AD

tan(86.4) = h/x

x*tan(86.4) = h

h = x*tan(86.4)

We'll use this later in the substitution below.

--------------------

Now move onto triangle BCD. For the reference angle B = 85, we can use the tangent rule to say

tan(angle) = opposite/adjacent

tan(B) = CD/DB

tan(B) = CD/(DA+AB)

tan(85) = h/(x+60)

tan(85)*(x+60) = h

tan(85)*(x+60) = x*tan(86.4) ............. apply substitution; isolate x

x*tan(85)+60*tan(85) = x*tan(86.4)

60*tan(85) = x*tan(86.4)-x*tan(85)

60*tan(85) = x*(tan(86.4)-tan(85))

x*(tan(86.4)-tan(85)) = 60*tan(85)

x = 60*tan(85)/(tan(86.4)-tan(85))

x = 153.612786190499

--------------------

We'll use this approximate x value to find h

h = x*tan(86.4)

h = 153.612786190499*tan(86.4)

h = 2441.60531869599

h = 2441.61 km is how high the satellite is above the ground.

Return to triangle ACD. We'll use the cosine rule to determine the length of the hypotenuse AC

cos(angle) = adjacent/hypotenuse

cos(A) = AD/AC

cos(86.4) = x/AC

cos(86.4) = 153.612786190499/AC

AC*cos(86.4) = 153.612786190499

AC = 153.612786190499/cos(86.4)

AC = 2446.43279498247

AC = 2446.43 km is the distance from the satellite to station A.

6 0

3 years ago