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3 years ago

Solve this system of equations using the addition method.

Mathematics

1 answer:

damaskus [11]3 years ago

6 0

Eqt 1 = 4a-5b=7
eqt 2 = 4a+5b=17
eqt1+eqt2= 8a=24
a=3 then 4*3-5b=7
so b=1

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At Friday's basketball game, there were 24 more than half the number of fans at Saturday's game. There were "f" fans at Saturday

Lady bird [3.3K]

<h3>- - - - - - - - - - - - - - - ~Hello There!~ - - - - - - - - - - - - - - - </h3>

➷ The expression would be:

$(\frac{f}{2}) + 24$

➶ Hope This Helps You!

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4 0

3 years ago

Read 2 more answers

(1 - cosx) (1 + 1/cosx) = sinxtanx

Nataly [62]

Answer:

cos x ≠ 0 ⇔ x ≠ $\frac{pi}{2}+k.pi$ ; k ∈ N

$(1-cosx)(1+\frac{1}{cosx})=sinx.tanx\\\\(1-cosx)(\frac{cosx+1}{cosx})=sinx.\frac{sinx}{cosx}\\\\ \frac{1-cos^{2} x}{cosx} =\frac{sin^{2}x }{cosx}\\\\=>1-cos^{2}x=sin^{2}x$

<=> cos²x + sin²x = 1

⇔ 1 = 1

=> x = { R \ (pi/2 + k.pi); k ∈ N}

Step-by-step explanation:

5 0

3 years ago

The center of a circle is located at (3, 8), and the circle has a radius that is 5 units long. What is the general form of the e

babymother [125]

The answer is A. To understand that, you need to put it in order by the x's and the y's to get x^2-6x + y^2-16y = -48. Now complete the square on both the x and the y terms to get (x^2-6x+9) +(y^2-16y+64) = -48+9+64. Rewriting that in vertex form on the left and doing the math on the right gives you
(x-3)^2 + (y-8)^2 = 25, which shows you a center of (3,8) and a radius of 5.

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3 years ago

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Solve for b.<br> 8^b-1=2^4b+4<br> b=_____

777dan777 [17]

I hope this helps you

7 0

3 years ago

In a random sample of 26 residents of the state of Montana, the mean waste recycled per person per day was 2.8 pounds with a sta

Rainbow [258]

Answer:

The critical value that should be used in constructing the confidence interval is T = 1.316.

The 80% confidence interval for the mean waste recycled per person per day for the population of Montana is between 2.741 pounds and 2.859 pounds.

Step-by-step explanation:

We have the standard deviation for the sample, which means that the t-distribution is used to solve this question.

The first step to solve this problem is finding how many degrees of freedom, we have. This is the sample size subtracted by 1. So

df = 26 - 1 = 25

80% confidence interval

Now, we have to find a value of T, which is found looking at the t table, with 25 degrees of freedom(y-axis) and a confidence level of $1 - \frac{1 - 0.8}{2} = 0.9$ . So we have T = 1.316

The critical value that should be used in constructing the confidence interval is T = 1.316.

The margin of error is:

$M = T\frac{s}{\sqrt{n}} = 1.316\frac{0.23}{\sqrt{26}} = 0.059$

In which s is the standard deviation of the sample and n is the size of the sample.

The lower end of the interval is the sample mean subtracted by M. So it is 2.8 - 0.059 = 2.741 pounds

The upper end of the interval is the sample mean added to M. So it is 2.8 + 0.059 = 2.859 pounds.

The 80% confidence interval for the mean waste recycled per person per day for the population of Montana is between 2.741 pounds and 2.859 pounds.

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3 years ago