Frank deposits his savings at the bank. After 3 years, it has earned $102 in interest, at a simple

Airida [17]

Step-by-step explanation:

→ 42 = 7u - u

→ 42 = 6u

→ 42/6 = u

→ 7 =u or U = 7

hope this answer helps you dear....take care and may u have a great day ahead!

4 0

3 years ago

Sally has 10 pounds she wants to buy 28 cans of soda which cost 28p each does she have enough money

Vladimir79 [104]

Answer:

Yes, Sally has enough money to buy 28 cans of soda.

Step-by-step explanation:

Yes, because £10 = 1000p

1000p / 28p = 35 cans

35 cans < 28 cans

So Sally has enough money for 28 cans.

4 0

2 years ago

Ebba is buying bulk fabric.

-Dominant- [34]

Answer:

To find the cost per yard, divide the cost by the amount:

p: 6.25 / 6.5 = 0.96 --> The cost per yard is $0.96

r: 3 /4 = 0.75 --> The cost per yard is $0.75

b: 8.1 /8.5 = 0.95 --> The cost per yard is $0.95

s: 7.2 / 6 = 1.2 --> The cost per yard is $1.20

In order from cheapest to most expensive:

Red

Brown

Purple

Silver

8 0

3 years ago

What is the area of the triangle? (Pls help thx)

Anna [14]

To solve for the area of the triangle
Use the formula 1/2(base *height)
1/2 * 17* 4
68/2
34

I believe the area of the triangle is therefore 34ft

5 0

3 years ago

) Use the Laplace transform to solve the following initial value problem: y′′−6y′+9y=0y(0)=4,y′(0)=2 Using Y for the Laplace tra

artcher [175]

Answer:

$y(t)=2e^{3t}(2-5t)$

Step-by-step explanation:

Let Y(s) be the Laplace transform Y=L{y(t)} of y(t)

Applying the Laplace transform to both sides of the differential equation and using the linearity of the transform, we get

L{y'' - 6y' + 9y} = L{0} = 0

(*) L{y''} - 6L{y'} + 9L{y} = 0 ; y(0)=4, y′(0)=2

Using the theorem of the Laplace transform for derivatives, we know that:

$\large\bf L\left\{y''\right\}=s^2Y(s)-sy(0)-y'(0)\\\\L\left\{y'\right\}=sY(s)-y(0)$

Replacing the initial values y(0)=4, y′(0)=2 we obtain

$\large\bf L\left\{y''\right\}=s^2Y(s)-4s-2\\\\L\left\{y'\right\}=sY(s)-4$

and our differential equation (*) gets transformed in the algebraic equation

$\large\bf s^2Y(s)-4s-2-6(sY(s)-4)+9Y(s)=0$

Solving for Y(s) we get

$\large\bf s^2Y(s)-4s-2-6(sY(s)-4)+9Y(s)=0\Rightarrow (s^2-6s+9)Y(s)-4s+22=0\Rightarrow\\\\\Rightarrow Y(s)=\frac{4s-22}{s^2-6s+9}$

Now, we brake down the rational expression of Y(s) into partial fractions

$\large\bf \frac{4s-22}{s^2-6s+9}=\frac{4s-22}{(s-3)^2}=\frac{A}{s-3}+\frac{B}{(s-3)^2}$

The numerator of the addition at the right must be equal to 4s-22, so

A(s - 3) + B = 4s - 22

As - 3A + B = 4s - 22

we deduct from here

A = 4 and -3A + B = -22, so

A = 4 and B = -22 + 12 = -10

It means that

$\large\bf \frac{4s-22}{s^2-6s+9}=\frac{4}{s-3}-\frac{10}{(s-3)^2}$

and

$\large\bf Y(s)=\frac{4}{s-3}-\frac{10}{(s-3)^2}$

By taking the inverse Laplace transform on both sides and using the linearity of the inverse:

$\large\bf y(t)=L^{-1}\left\{Y(s)\right\}=4L^{-1}\left\{\frac{1}{s-3}\right\}-10L^{-1}\left\{\frac{1}{(s-3)^2}\right\}$

we know that

$\large\bf L^{-1}\left\{\frac{1}{s-3}\right\}=e^{3t}$

and for the first translation property of the inverse Laplace transform

$\large\bf L^{-1}\left\{\frac{1}{(s-3)^2}\right\}=e^{3t}L^{-1}\left\{\frac{1}{s^2}\right\}=e^{3t}t=te^{3t}$

and the solution of our differential equation is

$\large\bf y(t)=L^{-1}\left\{Y(s)\right\}=4L^{-1}\left\{\frac{1}{s-3}\right\}-10L^{-1}\left\{\frac{1}{(s-3)^2}\right\}=\\\\4e^{3t}-10te^{3t}=2e^{3t}(2-5t)\\\\\boxed{y(t)=2e^{3t}(2-5t)}$

5 0

3 years ago