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avatar+225 

can someone help me... i keep getting both wrong 

 

Sketch a net of each regular pyramid. Then use the net to find the surface area of the pyramid.

 

 Sep 4, 2018
 #1
avatar+4221 
+2

Oh, the net! Sorry, can't do it here!

(a): Base: 10*10=100u^2. 4 of the same triangle faces, so 4*(1/2*10*20)=4*100=400u^2. 

Therefore, 100u^2+400u^2=500u^2!

 

(b): Base: 1/2*5.2*6=5.2*3=15.6, and looks like 3 of the same faces, with bases of 6(equilateral triangle), 3*(1/2*9*6)=3*27=81u^2, so 15.6u^2+81u^2=96.6u^2.

 

I might be wrong, someone please check! 

 Sep 4, 2018
 #2
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+1

You are right 

Guest Sep 4, 2018

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