Answer:
a) 300
b) 900
Step-by-step explanation:
The length of the rectangle is 5 and the width is 3...
But since the rectangles are connected together, we could just work the problem like this:
5 x 2 = 10
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3 x 5 = 15
15 x 2 = 30
The surface area of the shape is 10 x 30 = 300
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If the dimensions of the box were tripple, we would need to multiply the surface area by 3:
300 x 3 = 900
For the second question, the answer would be 900
Hope this helped you :-)
to get the equation of any straight line, we simply need two points off of it, let's use the ones in the picture below.

the sign would probably be a negative. imagine this - - - - - - and then + + +, cancel out the negatives and plus then you are left with more negatives than positive so the sign will take the negative sign.