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# Making a scale drawing

## Thuyết minh video

Cole is an urban planner he wants to create a small scale drawing of a city block the block is a square with an area of 8100 square meters create a scale drawing of the block using a scale factor of 0.1 so the first thing we could think about they give us the area of the block and it's a square block so it has the same length and width so we could use that information to figure out the length and width of that block so if it's a square so let's imagine a square block right over here and that this is I guess we'd call that the length and then this is also going to be the length it's going to be the same dimensions we know that the area is just going to be the length times the length the length times the length is going to be equal to 80 100 or 8100 or we could say that our length squared is going to be equal to 8100 so what time's itself is equal to 8100 well the 81 might jump out at you the 81 might jump out at you we know that 9 times 9 we know that 9 times 9 is equal to 81 but then we have these two zeros right over here but if we gave each of these 9s a zero then we'll end up with two zeros in the product so 90 x 90 is equal to 8100 so now we know the dimensions of this square block it's a 90 meter by 90 meter square block it's my best attempt to draw my best attempt to draw a square block now that's the actual square block it let me draw it a little bit more like a square my one first drawing looks a little bit too much like a rhombus so here you go a little bit better attempt at a square now we want to create a scale drawing of the block using a scale factor of 0.1 so the actual block once again is 90 meters by 90 meters but in our scale drawing and I'll do this in this purple color and our scale drawing we essentially want each of the dimensions to be 1/10 of their original of their original dimensions so we could take the scale factor and multiply it by each of these dimensions right over here so ninety times 0.1 well that's just going to be nine this right over here is 1/10 1/10 of ninety meters is going to be nine meters and so this when we draw the scale drawing at the scale that kool intends to draw it at we would draw nine meters by nine meters and so let's go to the actual tool and draw a nine meter by nine meter square our nine by nine square we can assume that the units here are in terms of meters so let's see I can draw a net dimension okay oops all right of nine there and let me use my mouse instead of my pen tool it'll be easier and then let me make this nine this let's see this side nine and then I can make this side nine and then we are all set it's a square we see we have four right angles and now we can check our answer and we got it right