All categories

3 years ago

I need help with 15 please ASAP!!!!!!

Mathematics

1 answer:

Lady bird [3.3K]3 years ago

6 0

Answer:

x must equal 5 and y must equal 2

therefore,

5a + 2b = 23 and

5a - 2b = 7.

I'm gonna take 5a + 2b = 23 and add 7 to each side:

5a + 2b + 7 = 30

and substitute 5a -2b in for 7 on the left side:

5a + 2b + (5a-2b) = 30

10a = 30

a = 3

Now we know a. Now take

5a -2b = 7

and substitute in 3 for a

5*(3) - 2b = 7

15 -2b = 7

8 = 2b

b = 4

a = 3 and b = 4

Step-by-step explanation:

You might be interested in

The sum of 30 times (1/3)^(n-1) from 1 to infinity

sergeinik [125]

Let

$S_n=\displaystyle1+\frac13+\frac1{3^2}+\cdots+\frac1{3^n}$

Then

$\dfrac13S_n=\displaystyle\frac13+\frac1{3^2}+\frac1{3^3}+\cdots+\frac1{3^{n+1}}$

and

$S_n-\dfrac13S_n=\dfrac23S_n=1-\dfrac1{3^{n+1}}\implies S_n=\dfrac32-\dfrac1{2\cdot3^n}$

and as $n\to\infty$ , we end up with

$\displaystyle\lim_{n\to\infty}S_n=\lim_{n\to\infty}\sum_{i=1}^{n+1}\frac1{3^{i-1}}=\lim_{n\to\infty}\left(\frac32-\frac1{2\cdot3^n}\right)=\frac32$

So we have

$\displaystyle\sum_{n=1}^\infty30\left(\frac13\right)^{n-1}=30\cdot\frac32=45$

8 0

3 years ago

Determine what type of model best fits the given situation a population of wolves is presently at 500 and is decreasing by 10% e

miskamm [114]

Answer:

B. Exponential

Step-by-step explanation:

The annual wolf population in each year is

w = 500 500(0.9) 500(0.9)² 500(0.9)³ …

n = 1 2 3 4 …

The model is w = 500(0.9)ⁿ⁻¹.

This is an exponential model, because the independent variable is in an exponent.

6 0

3 years ago

Read 2 more answers

What is the 31st term of the arithmetic sequence for 1.77, 1.92,2.07

natita [175]

Given that sequence 1.77, 1.92,2.07 is arithmetic sequence.

Using that we have to find 31st term.

To find that we can use nth term formula of arithmetic sequence which is given by:

$t_n=a_1+(n-1)d$

where n is the number of term so n=31

t_n indicates nth term

a_1 is the first term so a_1=1.77

r is the common difference which is given by difference of consecutive terms

then r=1.92-1.77=0.15

Now plug these values into above formula

$t_n=a_1+(n-1)d$

$t_{31}=1.77+(31-1)*0.15$

$t_{31}=1.77+(30)*0.15$

$t_{31}=1.77+4.5$

$t_{31}=6.27$

Hence final answer is 6.27.

8 0

4 years ago

Is 20 hundredths equal to 2 thousandths

tester [92]

Hello, you are asking of 20 hundredths are equal to 2 thousandths.

First of all, 1 thousandth = 1/1000 = 0,001

So, 2 thousandths = 2/1000 = 0,002

And 1 hundredth = 1/100 = 0,01

So, 20 hundredths = 20/100 = 0,2

0,2 is ≠ 0,002

So 20 hundredths are not equal to 2 thousandths

8 0

4 years ago

The table shows ordered pairs of the function . What is the value of y when ?

LiRa [457]

Answer:

(B) -8

Step-by-step explanation:

Given the 2-column table below:

$\left|\begin{array}{c|c}x&y\\--&--\\-3&14\\-1&10\\1&6\\4&0\\8&?\\10&-12\end{array}\right|$