I really need HELP I have 10 minutes to answer!!!!!

Find the 15th term of this arithmetic sequence for 20,26,32,38,44

olga2289 [7]

Answer:

104

Step-by-step explanation:

There are two ways to do it, though we need to know how it is affected.

20+6=26

26+6=32

32+6=38

38+6=44

Thus, you are adding 6 for each term.

1. You do it manually...(yes.)

I'll number it one by one

1.20

2.26

3.32

4.38

5.44

6.50

7.56

8.62

9.68

10.74

11.80

12.86

13.92

14.98

15.104

The 15th term is 104.

2. This method is easier. As shown above, there is a pattern. We can apply it using this formula:
20+6(n-1)

You can get this formula from the facts that:
-you start off with an additional added 8

-you add 6 every time

-if we do it 6n then it would be incorrect, with an extra 6 for each

-the formula is correct; you can test it for terms 2,3,4,5 like this:

20+6=26

20+2x6=32

20+3x6=38

20+4x6=44

To find the 15th term, you can:

20+14x6=20+84=104.

5 0

2 years ago

Use triangle ABC drawn below & only the sides labeled. Find the side of length AB in terms of side a, side b & angle C o

Brrunno [24]

Answer:

$AB = \sqrt{a^2 + b^2-2abCos\ C}$

Step-by-step explanation:

Given:

The above triangle

Required

Solve for AB in terms of a, b and angle C

Considering right angled triangle BOC where O is the point between b-x and x

From BOC, we have that:

$Sin\ C = \frac{h}{a}$

Make h the subject:

$h = aSin\ C$

Also, in BOC (Using Pythagoras)

$a^2 = h^2 + x^2$

Make $x^2$ the subject

$x^2 = a^2 - h^2$

Substitute $aSin\ C$ for h

$x^2 = a^2 - h^2$ becomes

$x^2 = a^2 - (aSin\ C)^2$

$x^2 = a^2 - a^2Sin^2\ C$

Factorize

$x^2 = a^2 (1 - Sin^2\ C)$

In trigonometry:

$Cos^2C = 1-Sin^2C$

So, we have that:

$x^2 = a^2 Cos^2\ C$

Take square roots of both sides

$x= aCos\ C$

In triangle BOA, applying Pythagoras theorem, we have that:

$AB^2 = h^2 + (b-x)^2$

Open bracket

$AB^2 = h^2 + b^2-2bx+x^2$

Substitute $x= aCos\ C$ and $h = aSin\ C$ in $AB^2 = h^2 + b^2-2bx+x^2$

$AB^2 = h^2 + b^2-2bx+x^2$

$AB^2 = (aSin\ C)^2 + b^2-2b(aCos\ C)+(aCos\ C)^2$

Open Bracket

$AB^2 = a^2Sin^2\ C + b^2-2abCos\ C+a^2Cos^2\ C$

Reorder

$AB^2 = a^2Sin^2\ C +a^2Cos^2\ C + b^2-2abCos\ C$

Factorize:

$AB^2 = a^2(Sin^2\ C +Cos^2\ C) + b^2-2abCos\ C$

In trigonometry:

$Sin^2C + Cos^2 = 1$

So, we have that:

$AB^2 = a^2 * 1 + b^2-2abCos\ C$

$AB^2 = a^2 + b^2-2abCos\ C$

Take square roots of both sides

$AB = \sqrt{a^2 + b^2-2abCos\ C}$

6 0

3 years ago

An escalator lifts people to the second floor of a building, 21 ft above the first floor. the escalator rises at a 30 degree ang

Ira Lisetskai [31]

We use the trigonometric function for this case. An escalator is an inclined path. We form a right triangle since we have given the value of the height. The height from the first floor to second floor is called the adjacent while the travelled distance of the people is called the hypothenuse. We use cosine function because we are given in terms of adjacent and hypothenuse. The ratio of cosine function is
cos x = a/h
where x is the angle
Solving for h,
h = a/(cos x) = 21/(cos 30) = 24.25 ft

7 0

2 years ago

Help plz!!!!!!!!! I need help please!!!

KengaRu [80]

8. commutative property of multiplication
9. associative property of multiplication
10.Multiplicative Property of Zero
11.Identity Property of Multiplication
12. commutative property of addition
13.associative property of multiplication
14.Identity Property of Addition
15. commutative property of addition
16. commutative property of multiplication
17.associative property of addition
18.Identity Property of Multiplication
19.associative property of addition
20.Identity Property of Addition
21.Multiplicative Property of Zero
22.associative property of multiplication

5 0

2 years ago

Please help me, very important 20 points!

kipiarov [429]

x=96

all interior angles equal 180

Subtract exterior andgles by 180 to get interior angles because they are supplementary

180-134=46

180-130=50

Get the third angle inside the triangle

180-50-46=84

subtract by 180 to get x because they are supplementary

180-84=96

Therefore x =96

4 0

2 years ago