## Welcome to H3 Maths

Blog Support for Growing Mathematicians

## Posts tagged with measuring

### Why don’t tape measures show √2?

March3

Your boss asks you to cut a length of wood exactly to √2. So, you get out your tape measure and ….what? There is NO √2! There should be though? After all, √2 is an exact length!! It was worked out on a calculator so you should be able to measure it? Why don’t rulers […]

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### Sine Method used to measure tallest tree

January23

Scientists recently measured the tallest tree in New Zealand at just over 81 metres. How did they do this? Using lasers and the Sine method – that is, the Sine of the angle formed by the lasers gave the height/hypotenuse. Read more here. (Note: This image is not of the tallest tree but gives some […]

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#### Post Support

10 x 9 x 8 + (7 + 6) x 5 x 4 x (3 + 2) x 1 = 2020

NCEA Level 2 Algebra Problem. Using the information given, the shaded area = 9, that is:
y(y-8) = 9 –> y.y – 8y – 9 =0
–> (y-9)(y+1) = 0, therefore y = 9 (can’t have a distance of – 1 for the other solution for y)
Using the top and bottom of the rectangle,
x = (y-8)(y+2) = (9-8)(9+2) = 11
but, the left side = (x-4) = 11-4 = 7, but rhs = y+? = 9+?, which is greater than the value of the opp. side??
[I think that the left had side was a mistake and should have read (x+4)?]