Answer:
The surface area of the lower rectangle is 20cm x 4cm= 80 square cm
the surface area of the two triangles is 12 square centimetres
the surface area of one of the top rectangular faces is 20×5= 100 square centimetres
the surface area of the other is 20×3= 60 square centimetres
80+12+60+100=252 square centimetres is the surface area of the polyhydron
Answer:
43
Step-by-step explanation:
90-47=43
Answer:
The first term should be positive
She did not distribute the -4 properly
She added
to negative -4 instead of multiplying
Step-by-step explanation:
In order to tell where she is wrong we should solve the question our selves. we are going to get the following......

So now we see that the three things she did wrong are.
The first term should be positive
She did not distribute the -4 properly
She added
to negative -4 instead of multiplying
Hope this helps :)