math
posted by Octivia .
A ladder that is 12,5m long rests against a wall with its foot 7,5m away from the wall.How far the ladder reaches up the wall?

Use the Pythagorean Theorem and solve for b.
a^2 + b^2 = c^2
7.5^2 + b^2 = 12.5^2
56.25 + b^2 = 156.25
b^2 = 156.25  56.25
b^2 = 100
b = 10 
The foot of the ladder in 4.2 above moves 4m closer to the wall.How much further will the ladder now reach up the wall?

Use the Pythagorean theorem as I showed you above.

Thank you

You're welcome.
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