Lin Created a scaled copy of triangle A with an area of 72 units

A bag contains yellow marbles in red marbles 65 in total. The number of yellow marbles is five more than four times the number o

antoniya [11.8K]

Answer: there would be 52 yellow marbles

Step-by-step explanation:

Ok we know that there is 65 marbles in total? Right? So then we’d take 65 and think, what could we divide this by and start guessing and estimating numbers. (I guessed 5, one because it’s divisible by 65, two there is 5 times more yellow marbles than red marbles.) So 5 divided by 65 is 13. But, in order to find the amount of yellow marbles, we need to subtract the whole number by the amount of red marbles. (So 65-13 =?) if you subtract that you get 52 yellow marbles. :)

7 0

2 years ago

What is 7 1/5 - 6 2/5 =?

poizon [28]

Answer:

0.8

Step-by-step explanation:

7 1/5 - 6 2/5 = 0.8

5 0

3 years ago

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

2 years ago

Is there a formula for problems like these? How do I even begin to solve it?

Pachacha [2.7K]

Well, they're saying 9 with an exponet of 2 multiplied by something equals 27..... Hmmm.....

5 0

2 years ago

Ms.Groves has trays of paint for students in her art class.each tray has 5 colors.one of the colors is purple.what fraction of t

seropon [69]

<span>So we need to find the fraction of many times does purple show up in 20 trays in which every tray has 5 colors. To find the answer we need to find the overall number of all colors and that is 20 trays * 5 colors and that equals to 100 colors. So purple shows 20 times and 20/100 is 1/5 when we simplify the fraction. </span>

4 0

2 years ago

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