Question

Please help thank you.

Answer 1

Hey Madoudou!

Let me try my best....

Ok so we have the length which is 14 cm

And the width is 7 cm

and the height is 1.66 cm

We need to find the lateral area.

The formula for that is:

Lateral Area = 2lh + 2wh

= 2(14cm)(1.66cm) + (2)(7cm)(1.66cm)
= 46.48 cm^2 + 23.24 cm^2
= 69.72 cm^2
As you can see, they don't give the options in decimal. So we have to take the one that is near 69.7 which is 70 cm^2

Now let's find the surface area.

The formula is:

SA = 2(wl + hl + hw)

SA= 2(7cm * 14) + 2(1.66cm * 14cm) + 2(1.66cm * 7cm)

SA = 196 cm^2 + 46.48 cm^2 + 23.24 cm^2

SA = 265.72 cm^2

The nearest number to 265.7 is 266

Thus,

The correct answer is option D

Let me know if you have any questions :)

Answer 2

The lateral area is the same as the as the surface area without the area of the bases.
In this solid, the bases are the 14 by 7 rectangles, so those are the only 2 sides that will be excluded in the lateral area.

Add the areas of the other rectangles except those two to find the lateral area.


`(1.66*14)+(1.66*14)+(1.66*7)+(1.66*7)`

`=69.72`

The lateral area is 69.72 square centimeters.

We already have the lateral area, so finding the total surface area will be quite simple. Just find the area of the two bases and add them to the lateral area.


`(14*7)+(14*7)+69.72`

`=265.72`

The total surface area is 265.72 square centimeters.

Rounding everything, the answer is 70 cm² and 266 cm² (last answer choice). Hope this helps! :)