A 10-foot ladder leans against a wall with its foot braced 3 feet from wall’s base. How far up the wall does the ladder reach?

Question

A 10-foot ladder leans against a wall with its foot braced 3 feet from wall’s base.  How far up the wall does the ladder reach?

jim_thompson5910 · Answer

Hint:

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jim_thompson5910 · Answer

use the pythagorean theorem to solve for x

a^2 + b^2 = c^2

x^2 + 3^2 = 10^2

x^2 + 9 = 100

I'll let you finish

anonymous · Answer

$$100-9= 81 =\sqrt{9} ?$$

anonymous · Answer

9.53

anonymous · Answer

>.<
Dang it, how?

anonymous · Answer

I did reverse Pythagorean theorem $$c ^{2} - b ^{2} = a ^{2}$$

jim_thompson5910 · Answer

$$\Large x^2 + 9 = 100$$

$$\Large x^2 = 100-9$$

$$\Large x^2 = 91$$

$$\Large x = \sqrt{91}$$

$$\Large x \approx 9.53939201416946$$

anonymous · Answer

height  = sqrt(100 - 9 )
= sqrt (91)
approx 9.53

anonymous · Answer

I was told to leave it in radical form

anonymous · Answer

oh well yeah 9 then

anonymous · Answer

Yay! Thank you everyone

jim_thompson5910 · Answer

so leave it as $$\Large \sqrt{91}$$

anonymous · Answer

Just to let it be known I realized that I was wrong. I just realized that I got 81 and it should have been 91, then I finished the problem and it came out to be what you guys got , 9.53 .. thank you for the help [: