Explain why errors cannot be avoided

The following picture is a square pyramid where DE=8 cm and m∠ADE=60°.

Goryan [66]

Given:

The length of DE is 8 cm and the measure of ∠ADE is 60°.

We need to determine the surface area of the pyramid.

Length of AD:

The length of AD is given by

$cos 60^{\circ}=\frac{FD}{8}$

$4=FD$

Length of AD = 8 cm

Slant height:

The slant height EF can be determined using the trigonometric ratio.

Thus, we have;

$sin \ 60^{\circ}=\frac{EF}{8}$

$sin \ 60^{\circ} \times 8=EF$

$\frac{\sqrt{3}}{2} \times 8=EF$

$4\sqrt{3}=EF$

Thus, the slant height EF is 4√3

Surface area of the square pyramid:

The surface area of the square pyramid can be determined using the formula,

$SA=Area \ of \ square + \frac{1}{2} (Perimeter \ of \ base ) (slant \ height)$

Substituting the values, we have;

$SA=8^2+\frac{1}{2}(8+8+8+8)(4 \sqrt{3})$

$SA=64+\frac{1}{2}(32)(4 \sqrt{3})$

$SA=64+(16)(4 \sqrt{3})$

$SA=64+64 \sqrt{3}$

The exact form of the area of the square pyramid is $64+64 \sqrt{3}$

Substituting √3 = 1.732 in the above expression, we have;

$SA = 64 + 110.848$

$SA = 174.848$

Rounding off to one decimal place, we get;

$SA = 174.8$

Thus, the area of the square pyramid is 174.8 cm²

7 0

3 years ago

Read 2 more answers

A car dealership sold 480 vehicles last year. Of these vehicles, 15% were minivans.

natulia [17]

You can use my photo as reference but its going to be 15/100 of 480

7 0

3 years ago

Keli has 26 roses and 73 carnations. She will put an assortment of 6 flowers in each vase. How many vases will she need for her

Irina18 [472]

Add 26 and 73 = 99 then divide 99 by 6 = 16.5 which is 17 vases

8 0

3 years ago

Lance says that you can compare any decimal numbers the way that you alphatbetize words you can tell which number is first by co

Afina-wow [57]

Answer:

No, Lance's thinking is wrong because you cannot compare decimal numbers with alphabetizing words. For example, if we compare 37.6 to 7.42 using the method of Lance, we would probably say 37.6 is less than 7.42 because 3 is less than 7. But it is wrong. The 3 in 37.6 is in the tens place. On the other hand, 7.42 contains no tense. Therefore, 37.6 is actually higher.

Step-by-step explanation:

No, Lance's thinking is wrong because you cannot compare decimal numbers with alphabetizing words. For example, if we compare 37.6 to 7.42 using the method of Lance, we would probably say 37.6 is less than 7.42 because 3 is less than 7. But it is wrong. The 3 in 37.6 is in the tens place. On the other hand, 7.42 contains no tense. Therefore, 37.6 is actually higher.

6 0

3 years ago

A what is formed by two number lines that intersect at a right angle?

Schach [20]

Answer: Coordinate Plane is formed by two number lines that intersect at a right angle.

3 0

3 years ago