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3 years ago

15

Solve this inequality for x. 81-1 1/5 x <55

1 answer:

katen-ka-za [31]3 years ago

4 0

Answer:

A. x > 21 2/3

Step-by-step explanation:

x is greater than 21 and two thirds

i did the math :]

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Help help me please

LuckyWell [14K]

If they are parallelogram

2x/10=4y

3y/24=6x

get the values for xand y i think u can solve it

7 0

3 years ago

How do I solve this??

Strike441 [17]

Answer:

r = -1/2

Step-by-step explanation:

3(5 + 4r) = -18r

15 +12r = -18r by distributive property

15 = -12r - 18r

15 = -30r

r = - 1/2r

4 0

3 years ago

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Texas has 254 counties . California has 58 counties . Florida has 67 counties. How many more counties dose Texas have then the n

zzz [600]

<u><em>The answer is 129 </em></u><em> i hope this helps </em>

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5 0

3 years ago

Read 2 more answers

Apply the method of undetermined coefficients to find a particular solution to the following system.wing system.

jarptica [38.1K]

$y''-y'+y=\sin x$

The corresponding homogeneous ODE has characteristic equation $r^2-r+1=0$ with roots at $r=\dfrac{1\pm\sqrt3}2$ , thus admitting the characteristic solution

$y_c=C_1e^x\cos\dfrac{\sqrt3}2x+C_2e^x\sin\dfrac{\sqrt3}2x$

For the particular solution, assume one of the form

$y_p=a\sin x+b\cos x$

${y_p}'=a\cos x-b\sin x$

${y_p}''=-a\sin x-b\cos x$

Substituting into the ODE gives

$(-a\sin x-b\cos x)-(a\cos x-b\sin x)+(a\sin x+b\cos x)=\sin x$

$-b\cos x+a\sin x=\sin x$

$\implies a=1,b=0$

Then the general solution to this ODE is

$\boxed{y(x)=C_1e^x\cos\dfrac{\sqrt3}2x+C_2e^x\sin\dfrac{\sqrt3}2x+\sin x}$

$y''-3y'+2y=e^x\sin x$

$\implies r^2-3r+2=(r-1)(r-2)=0\implies r=1,r=2$

$\implies y_c=C_1e^x+C_2e^{2x}$

Assume a solution of the form

$y_p=e^x(a\sin x+b\cos x)$

${y_p}'=e^x((a+b)\cos x+(a-b)\sin x)$

${y_p}''=2e^x(a\cos x-b\sin x)$

Substituting into the ODE gives

$2e^x(a\cos x-b\sin x)-3e^x((a+b)\cos x+(a-b)\sin x)+2e^x(a\sin x+b\cos x)=e^x\sin x$

$-e^x((a+b)\cos x+(a-b)\sin x)=e^x\sin x$

$\implies\begin{cases}-a-b=0\\-a+b=1\end{cases}\implies a=-\dfrac12,b=\dfrac12$

so the solution is

$\boxed{y(x)=C_1e^x+C_2e^{2x}-\dfrac{e^x}2(\sin x-\cos x)}$

$y''+y=x\cos(2x)$

$r^2+1=0\implies r=\pm i$

$\implies y_c=C_1\cos x+C_2\sin x$

Assume a solution of the form

$y_p=(ax+b)\cos(2x)+(cx+d)\sin(2x)$

${y_p}''=-4(ax+b-c)\cos(2x)-4(cx+a+d)\sin(2x)$

Substituting into the ODE gives

$(-4(ax+b-c)\cos(2x)-4(cx+a+d)\sin(2x))+((ax+b)\cos(2x)+(cx+d)\sin(2x))=x\cos(2x)$

$-(3ax+3b-4c)\cos(2x)-(3cx+3d+4a)\sin(2x)=x\cos(2x)$

$\implies\begin{cases}-3a=1\\-3b+4c=0\\-3c=0\\-4a-3d=0\end{cases}\implies a=-\dfrac13,b=c=0,d=\dfrac49$

so the solution is

$\boxed{y(x)=C_1\cos x+C_2\sin x-\dfrac13x\cos(2x)+\dfrac49\sin(2x)}$

7 0

3 years ago

Drag each real-world situation to the correct column to show whether it can be modeled by combining additive inverses to get 0.

Flauer [41]

Answer:

. An investment account earns 2.8% simple interest.

Since investment amount increases every year linearly, therefore, the modeled situation represents a LINEAR FUNCTION.

B). The price of a stock varies by 2.8% each week.

Since price of the stock may increase or decrease every week, therefore, this situation can't be modeled by any function.

Therefore, the answer is NEITHER.

C). An investment account earns 2.8% compound interest, compounded monthly.

Formula to get the value of the final amount in the account is,

Final value = Initial value ×

Here 't' = Duration of investment

It's an EXPONENTIAL FUNCTION.

Step-by-step explanation:

3 0

2 years ago