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Find x
the area of the end surface
the volume
the total surface

Find x the area of the end surface the volume the total surface-example-1
User Adam Keenan
by
2.5k points

1 Answer

19 votes
19 votes

Answer:

(i) x = 17 cm

(ii) one end: 360 cm²; both ends: 720 cm²

(iii) 14,400 cm³

(iv) 4000 cm²

Explanation:

You want the slant height, base area, volume, and total surface area of a trapezoidal prism with the base isosceles trapezoid having parallel base lengths of 32 and 16, and a height of 15. The distance between bases is 40. All units are cm.

(i) Slant height

If a center rectangle 16 cm wide and 15 cm high is cut from the base trapezoid, the remaining two triangles have a base of 8 cm and a height of 15 cm. The Pythagorean theorem can be used to find the slant height:

x² = a² +b²

x² = 8² +15² = 64 +225 = 289

x = √289 = 17

The slant height, x, is 17 cm.

(ii) Base area

The area of the base trapezoid is given by the formula ...

A = 1/2(b1 +b2)h

A = 1/2(32 +16)(15) = 360 . . . . square cm

The area of one end surface is 360 cm²; the total area of both end surfaces is 720 cm².

(iii) Volume

The volume of the prism is the product of the base area and the length of the prism.

V = Bh

V = (360 cm²)(40 cm) = 14,400 cm³

The volume of the trapezoidal prism is 14,400 cm³.

(iv) Total surface area

The lateral surface area of the prism is the product of the perimeter of the base and the distance between bases.

LA = Ph

LA = (32 +16 +2·17 cm)(40 cm) = 3280 cm²

The total surface area is the sum of the lateral area and the area of the two bases:

SA = LA +2B = (3280 cm²) + 2(360 cm²) = 4000 cm²

The total surface area of the prism is 4000 square centimeters.

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Additional comment

It appears that the top dashed line in the figure is drawn that way in error. It appears to identify a visible edge, so we expect it to be a solid line.

Find x the area of the end surface the volume the total surface-example-1
User Suriyan Suresh
by
3.3k points