3 years ago

What is the sum of the first 4 terms of the arithmetic

1 answer:

8 0

$a_6=8;\ a_{10}=13\\\\a_{10}-a_6=4r\\\\4r=13-8\\4r=5\ \ \ \ /:4\\r=1.25\\\\a_1=a_6-5r\\a_1=8-5\cdot1.25=8-6.25=1.75\\\\S_4=\frac{2a_1+(4-1)r}{2}\cdot4=(2a_1+3r)\cdot2=4a_1+6r\\\\S_4=4\cdot1.75+6\cdot1.25=7+7.5=14.5$

You might be interested in

How days Feb 7 through Dec 23 or to Feb 7?

miv72 [106K]

319 days to feb 10 months and 16days

4 0

2 years ago

Solve the equation for x. 2 3 x −1 9 x + 5 = 20 x =

zubka84 [21]

Answer:

5/2

Step-by-step explanation:

23x-19x+5=2x

23x-19x-2x=5

2x/2=5/2

x=5/2

3 0

2 years ago

Read 2 more answers

Y = -2x + 13 when x = 6

elena-14-01-66 [18.8K]

Answer: 1

Work: After plugging in the 6 in the X, the new equation is -2(6) + 13. After doing the multiplication of -2 and 6, you get -12. Add -12 + 13, and the answer (Or y) equals 1.

<em>I hope this helps, and Happy Holidays! :)</em>

6 0

2 years ago

Read 2 more answers

Consider an equilateral triangle that is small enough to fit in your pocket. Now consider an equilateral triangle that is big en

Simora [160]

Answer:

Step-by-step explanation:

First Question: Equilateral triangles all have the same interior angles. 60 degrees. Size does not make the angles bigger. It makes the sides bigger.

Second Question: No the size does not influence the size of the interior angle.

Third Question: That's true for all polygons. Size is not affect the interior angle size.

6 0