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help with geometry? and got a better answer
Response from Дима[+++]
1 A prism has all its side edges parallel. By the theorem If the plane is perpendicular to one of two parallel lines, then it is perpendicular to the other one also follows the proof of the statement of Problem 2 Let MAWSD the given pyramid Diagonals AC and BP intersect at O. From rectangular triangle ABB where AO=4 and DO=3 by Pythogoras theorem we find AD=5cm. From point O let us lower the height OK of triangle AOD onto AD. Then 3*4= 5*OK. Then OK=12/5= 2.4. Then area of the frame AMD=0,5*5*2,4= 6. side surface of pyramid=6*4=24sm3 square diagonal of rectangle is equal 36 +64= 100 then diagonal is 10 cm, and its half is 5 cm. we will find the height of pyramid by Pythagoras theorem H2= 169 -25=144. let's find the area of base, which is a parallellogram with sides 3cm and 8cm and angle 60 between them, then S=3*8*sin60=12V3 the full area of parallelepiped is equal 220 +12V3 +12V3= 220 + 24V3
1 A prism has all its side edges parallel. By the theorem If the plane is perpendicular to one of two parallel lines, then it is perpendicular to the other. Proof of Problem 2 Let MAWSD be the pyramid diagonals AC and BP intersect at O. From rectangular triangle ABB where AO=4 and DO=3 by Pythogoras theorem we find AD=5cm. From point O let's lower the height OK of triangle AOD onto AD. Then 3*4= 5*OK. Then OK=12/5= 2.4. Then area of the frame AMD=0,5*5*2,4= 6. side surface of pyramid=6*4=24sm3 square diagonal of rectangle is equal 36 +64= 100 then diagonal is equal 10sm, and its half is 5sm. we will find the height of pyramid by Pythagoras theorem H2= 169 -25=144. let's find the area of the base, which is a parallellogram with sides 3cm and 8cm and angle 60 between them, then S=3*8*sin60=12V3 the full area of the parallelepiped is 220 +12V3 +12V3= 220 + 24V3