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3 years ago

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

1 answer:

8 0

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

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The length of the base edge of a pyramid with a regular hexagon base is represented as x. The height of the pyramid is 3 times l

sergij07 [2.7K]

Answer:

(a)

h=3x

(b)

$A=\frac{\sqrt{3} }{4} x^2$

(c)

$A=\frac{3\sqrt{3} }{2} x^2$

(d)

$V=\frac{3\sqrt{3} }{2} x^3$ units^3

Step-by-step explanation:

We are given a regular hexagon pyramid

Since, it is regular hexagon

so, value of edge of all sides must be same

The length of the base edge of a pyramid with a regular hexagon base is represented as x

so, edge of base =x

b=x

Let's assume each blank spaces as a , b , c, d

we will find value for each spaces

(a)

The height of the pyramid is 3 times longer than the base edge

so, height =3*edge of base

height=3x

h=3x

(b)

Since, it is in units^2

so, it is given to find area

we know that

area of equilateral triangle is

$=\frac{\sqrt{3} }{4} b^2$

h=3x

b=x

now, we can plug values

$A=\frac{\sqrt{3} }{4} x^2$

(c)

we know that

there are six such triangles in the base of hexagon

So,

Area of base of hexagon = 6* (area of triangle)

Area of base of hexagon is

$=6\times \frac{\sqrt{3} }{4} x^2$

$=\frac{3\sqrt{3} }{2} x^2$

(d)

Volume=(1/3)* (Area of hexagon)*(height of pyramid)

now, we can plug values

Volume is

$=\frac{1}{3}\times\frac{3\sqrt{3} }{2} x^2\times (3x)$

$V=\frac{3\sqrt{3} }{2} x^3$ units^3

3 0

4 years ago

Read 2 more answers

What the correct answer is

Vesna [10]

Answer:

so the answer from paper is DC

4 0

3 years ago

Contrast and compare squares and rectangles

liberstina [14]

Answer:

I found this over the internet and hope it helps:

A rectangle is a quadrilateral with all four angles right angles. It follows form this that the opposite sides are parallel and of the same length. A square is a quadrilateral with all four angles right angles and all four sides of the same length.

Also note that a square is always a rectangle, but a rectangle is not always a square.

8 0

3 years ago

Read 2 more answers

Which place value contains the 7 in the quotient of 8,928 divided by 24?

Ainat [17]

Answer: 7 is in tens place

Step-by-step explanation: 8928 ÷ 24 = 372

Ones place - 2

Tens place - 7

Hundreds place - 3

The 7 is in the tens place