Question #f7144

1 Answer
Jan 18, 2018

See below.

Explanation:

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a)

Volume of a prism is given by:

Area of base x height.

color(blue)((2c-2)(3c-4))(2c2)(3c4)

b)

(2c-2)(3c-4)=color(blue)(6c^2-14c+8)(2c2)(3c4)=6c214c+8

c)

(2(2)-2)(3(2)-4)=color(blue)(4)(2(2)2)(3(2)4)=4

6(2)^2-14(2)+8=color(blue)(4)6(2)214(2)+8=4

d)

The surface area is the sum of all the areas of the 6 faces of the prism. Sides opposite each other have the same area, so there are 3 pairs of areas;

From diagram these are:

2xx(2c-2)(3c-4)=12c^2-28c+162×(2c2)(3c4)=12c228c+16

2xx(2c-2)(c+7)=4c^2+24c-282×(2c2)(c+7)=4c2+24c28

2xx(3c-4)(c+7)=6c^2+34c-562×(3c4)(c+7)=6c2+34c56

We add these results together:

color(white)(888)12c^2-28c+1688812c228c+16

color(white)(8888)4c^2+24c-2888884c2+24c28

color(white)(8888)6c^2+34c-5688886c2+34c56

=color(white)(8)color(blue)(22c^2+30c-68)=822c2+30c68