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2 years ago

The sum of the first 8 terms of a geometric sequence with 4 as the first term and a common ratio of 3 is

Mathematics

2 answers:

ki77a [65]2 years ago

7 0

9514 1404 393

Answer:

13120

Step-by-step explanation:

The sum of terms of a geometric series is ...

Sn = a1·(r^n -1)/(r -1)

You have n=8, a1=4, r=3, so the sum is ...

S8 = 4·(3^8 -1)/(3 -1) = 2(3^8 -1) = 13,120

olya-2409 [2.1K]2 years ago

6 0

Answer:

Step-by-step explanation:

hope it helps u too

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The number of students in the class (x) will be divided into teams of 4, except one team will have 5, resulting teams in all. Wr

Ierofanga [76]

Answer:

x = 4y + 5

Step-by-step explanation:

x represents the total students in the class. We don't know how many teams of four there will be, so we represent that with y. 4y represents the total students in teams of 4. We know there is one team of 5, so that is added to 4y.

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3 years ago

The pair of polygons is similar. Find the missing side measure. A) 7 B) 9 C) 13.5 D) 24

arlik [135]

Answer:

Step-by-step explanation:

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2 years ago

Read 2 more answers

Please help! question attached

Svetradugi [14.3K]

Answer:

36. y=x

37. x=4

38. y=3x-10

39. y=-25x+49

40. $y=-\dfrac{1}{18}x-\dfrac{89}{18}$

41. y=-x+3

Step-by-step explanation:

36. Parallel lines have the same slope. The slope of the line $y=x+42$ is $m=1,$ so the equation of a parallel line is

$y=x+b$

This line passes through the point (2,2), so its coordinates satisfy the equation:

$2=2+b\\ \\b=0$

and the equation of the line is $y=x$

37. The line $x=03$ is vertical ine, so parallel line is also vertical line with equation $x=a.$ Substitute the coordinates of the point (4,3):

$4=a$

hence the equation is $x=4$

38. Parallel lines have the same slope. The slope of the line $y=3x+24$ is $m=3,$ so the equation of a parallel line is

$y=3x+b$

This line passes through the point (2,-4), so its coordinates satisfy the equation:

$-4=3\cdot 2+b\\ \\b=-10$

and the equation of the line is $y=3x-10$

39. Parallel lines have the same slope. The slope of the line $y=-25x+35$ is $m=-25,$ so the equation of a parallel line is

$y=-25x+b$

This line passes through the point (2,-1), so its coordinates satisfy the equation:

$-1=-25\cdot 2+b\\ \\b=49$

and the equation of the line is $y=-25x+49$

40. Perpendicular lines have slopes satisfying $m_1\cdot m_2=-1$ Since the line $y=18x+26$ has the slope $m_1=18,$ perpendicular line has the slope $m_2 =-\dfrac{1}{18}.$

The equation is

$y=-\dfrac{1}{18}x+b$

This line passes through the point (1,-5), so its coordinates satisfy the equation:

$-5=-\dfrac{1}{18}\cdot 1+b\\ \\b=-5+\dfrac{1}{18}=-\dfrac{89}{18}$

and the equation of the line is $y=-\dfrac{1}{18}x-\dfrac{89}{18}$

41. Perpendicular lines have slopes satisfying $m_1\cdot m_2=-1$ Since the line $y=x+2$ has the slope $m_1=1,$ perpendicular line has the slope $m_2 =-1.$