Question 603665
A 4.5 metre ladder rests against a vertical wall with its feet on level ground 2.5 m from the wall.
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Draw the picture.
You have a right triangle with base = 2.5 and hypotenuse = 4.5
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(a) How high up the wall does it reach?

Use Pythagoras:
height^2 + base^2 = hyp^2
h^2 + 2.5^2 = 4.5^2
h^2 = 4.5^2 - 2.5^2
h^2 = 14 ft
h = sqrt(14) ft.
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(b) If the feet of the ladder are pushed 0.8 m closer to the wall, how much higher up the wall will it reach?
base = 2.5-0.8 = 1.7 ft
hypotenuse is still 4.5
h^2 = 4.5^2 - 1.7^2
h^2 = 17.36
h = sqrt(17.36)
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height has increased by sqrt(17.36)-sqrt(14) = 0.4249 ft.
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Cheers,
Stan H.
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