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3 years ago

Find the 87th term of this sequence: 157, 150, 143, ...

Mathematics

1 answer:

nirvana33 [79]3 years ago

7 0

Answer:

Step-by-step explanation:

$a_1=157\\a_2=150\\\\d=150-157=-7\\\\a_n=a_1+d(n-1)\\\\a_{87}=157+(-7)(87-1)=157-7\cdot86=-445$

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Which line from the excerpt is an example of objective language? In the course of the construction of the Bridge a number of liv

Svetlanka [38]

Answer:

Step-by-step explanation:

The answer is C

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3 years ago

Roger wants to carpet a rectangular room with length of 8 3/4 feet and a width of 9 1/3 feet. If he has 85 square feet of carpet

Dima020 [189]

Answer:

12.66 $ft^2$

Step-by-step explanation:

Given the dimensions of the room are $8\frac{3}{4}$ = $\frac{31}{4}$ and $9\frac{1}{3}$ = $\frac{28}{3}$ .

The area of the room = $length*width$

Area= $\frac{31}{4} *\frac{28}{3}$

Area=72.33 $ft^2$

The area of the carpet=85 $ft^2$

The area of carpet left= Total area of carpet - the area of the room

The area of carpet left= 85-72.33=12.66 $ft^2$

7 0

3 years ago

If tanA=a then find sin4A-2sin2A/ sin4A+2sin2A

anygoal [31]

Answer:

The value of the given expression is

$\frac{sin4A-2sin2A}{sin4A+2sin2A}=-a^2$

Step by step Explanation:

Given that $tanA=a$

To find the value of $\frac{sin4A-2sin2A}{sin4A+2sin2A}$

Let us find the value of the expression :

$\frac{sin4A-2sin2A}{sin4A+2sin2A}=\frac{2cos2Asin2A-2sin2A}{2cos2Asin2A+2sin2A}$ ( by using the formula $sin2A=2cosAsinA$ here A=2A)

$=\frac{2sin2A(cos2A-1)}{2sin2A(cos2A+1)}$

$=\frac{(cos2A-1)}{(cos2A+1)}$

$=\frac{(-(1-cos2A))}{(1+cos2A)}$ (using $sin^2A+cos^2A=1$ here A=2A)

$=\frac{-(sin^2A+cos^2A-(cos^2A-sin^2A))}{sin^2A+cos^2A+(cos^2A-sin^2A)}$ (using $cos2A=cos^2A-sin^2A$ here A=2A)

$=\frac{-(sin^2A+cos^2A-cos^2A+sin^2A)}{sin^2A+cos^2A+(cos^2A-sin^2A)}$

$=\frac{-(sin^2A+sin^2A)}{cos^2A+cos^2A}$

$=\frac{-2sin^2A}{2cos^2A}$

$=-\frac{sin^2A}{cos^2A}$

$=-tan^2A$ ( using $tanA=\frac{sinA}{cosA}$ here A=2A )

$=-a^2$ (since tanA=a given )

Therefore $\frac{sin4A-2sin2A}{sin4A+2sin2A}=-a^2$

6 0

3 years ago

What is the value of y in this system of equations: 3x + y = 9 y = –4x + 10 ?

Ahat [919]

3x + y = 9 (I)
y = –4x + 10 (II)
------------------------
 $\left \{ {{3x + y = 9 } \atop {y = -4x + 10 }} \right.$

Pass the incognito "4x" to the first term, changing the signal when changing sides.
-------------------------
simplify by (-1)
 $\left \{ {{3x + y = 9.(-1)} \atop {4x + y = 10 }} \right.$ 

-------------------------
 $\left \{ {{- 3x - \diagup\!\!\!\!y =-9} \atop {4x + \diagup\!\!\!\!y = 10}} \right. 
$

-------------------------
 $\left \{ {{- 3x = - 9} \atop {4x = 10}} \right.$ 

-----------
 $\boxed{x = 1}$ 

Substitute in equation (I) to find the value of "Y".

3x + y = 9 (I)
3*(1) + y = 9
3 + y = 9
y = 9 - 3
$\boxed{y = 6}$

Answer:
$\boxed{\boxed{ \left \ {{x=1} \atop {y=6}} \right. }}$

6 0

3 years ago

5a+8+(-2a)=-7 I need help with this question especially because of the parenthesis

Mashcka [7]

Answer:

5a+8+(-2a)=-7

5a+8-2a=-7

5a-2a=-7-8

3a=-15

3a/3=-15/3

a=-5

3 0

3 years ago

Read 2 more answers