I need help with this

[Micheal.]

I think this belongs in geometry. I found the area of the skinny rectangle on the left and it was 54.6 and then the big rectangles on the right were 133 each. Then I added the rectangle areas together but it's still wrong. I put the units too.

 

[Deleted member 4993]

I think this belongs in geometry. I found the area of the skinny rectangle on the left and it was 54.6 and then the big rectangles on the right were 133 each. Then I added the rectangle areas together but it's still wrong. I put the units too.

the dimensions of the rectangles are 9.5 x 14 and 10.3 x 14.

Those rectangles are not congruent!

 

[jonah2.0]

Beer induced observation follows.

I think this belongs in geometry. I found the area of the skinny rectangle on the left and it was 54.6 and then the big rectangles on the right were 133 each. Then I added the rectangle areas together but it's still wrong. I put the units too.

10.3 mm was presumably rounded off from [MATH]\sqrt{3.9^2+9.5^2}\approx10.269371938[/MATH]

 

[jalexandre]

The skinny rectangle on the left is 3.9 x 14, the rectangle in the middle is 9.5 x 14, and the one on the right is 10.3 x 14. Then the area of the two triangles combined would be the area of a rectangle with dimensions 3.9 x 9.5. If you add all of that up you should get the total surface area.