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3 years ago

How do you solve this systems of equations problem 2r +3s=-5 6s=2r

Mathematics

1 answer:

Yuri [45]3 years ago

7 0

Answer:

see explanation

Step-by-step explanation:

Given the 2 equations

2r + 3s = - 5 → (1)

6s = 2r → (2) ( divide both sides by 2 ), then

r = 3s

Substitute r = 3s into (1)

2(3s) + 3s = - 5

6s + 3s = - 5

9s = - 5 ( divide both sides by 9 )

s = - $\frac{5}{9}$

Substitute this value into either of the 2 equations and evaluate for r

Substituting into r = 3s, then

r = 3 × - $\frac{5}{9}$ = - $\frac{5}{3}$

Solution is r = - $\frac{5}{3}$ and s = - $\frac{5}{9}$

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I really need help please

Arturiano [62]

This is true. you don't need to provide a counterexample

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3 years ago

You just purchased two coins at a price of $670 each. Because one of the coins is more collectible, you believe that its value w

DerKrebs [107]

Answer:

The value of first coin will be $151.51 more than second coin in 15 years.

Step-by-step explanation:

You have just purchased two coins at a price of $670 each.

You believe that first coin's value will increase at a rate of 7.1% and second coin's value 6.5% per year.

We have to calculate the first coin's value after 15 years by using the formula

$A=P(1+\frac{r}{100})^{n}$

Where A = Future value

P = Present value

r = rate of interest

n = time in years

Now we put the values

$A=670(1+\frac{7.1}{100})^{15}$

$A=670(1+0.071)^{15}$

$A=670(1.071)^{15}$

A = (670)(2.797964)

A = 1874.635622 ≈ $1874.64

Now we will calculate the value of second coin.

$A=670(1+\frac{6.5}{100})^{15}$

$A=670(1+0.6.5)^{15}$

$A=670(1.065)^{15}$

A = 670 × 2.571841

A = $1723.13

The difference of the value after 15 years = 1874.64 - 1723.13 = $151.51

The value of first coin will be $151.51 more than second coin in 15 years.

8 0

3 years ago

What is 450 increased by 18%

Blababa [14]

450*(1+0.18)=531 hence 450 increased by 18% is 531

6 0

3 years ago

Read 2 more answers

(20 pts!) if the base of the roof has length 40 feet and x=30, which of the following gives the height of the roof?

musickatia [10]

Answer:

23.094 ft approximately

(If you want your answer in a different format, let me know please.)

Step-by-step explanation:

I would have solve this using tangent since the side opposite to x is asked for and the adjacent side to side is given as having a measurement of 40 ft.

But I think they want you to use the formula:

$l=\frac{b}{\cos(x)}$ .

$l=\frac{40}{\cos(30)}$

Input into calculator:

$l=46.188$ (approximation)

l represents the length of the roof.

So we have l=46.188 and b=40.

We must use the Pythagorean Theorem to find the height,h, for of the roof.

l is the hypotenuse.

$h^2+40^2=46.188^2$

$h^2+1600=2133.331$

Subtract 1600 on both sides:

$h^2=533.331$

Take square root of both sides:

$h=23.094$

The answer is 23.094 feet for the height that roof reaches on the building.

I want to show you another way:

$\tan(x)=\frac{\text{opposite}}{\text{adjacent}}$

$\tan(30)=\frac{h}{40}$

Multiply both sides by 40:

$40\tan(30)=h$

Input into calculator:

$23.094=h$

I didn't do it this way because your problem suggested you use their formula to find the height.

8 0

3 years ago

Read 2 more answers

Carly is constructing the inscribed circle for △MNP . She has already used her compass and straightedge to complete the part of

arlik [135]

The complete question in the attached figure

the answer is Place the point of the compass on point J and draw an arc in the interior of the triangle.

4 0

3 years ago