d) 10 cm, 15 cm, 20 cm to the top of a building 3 m high the foot of the wall is 4 m.

Ili kupata urefu wa upande $k$, tutatumia Theorem ya Pythagoras.
Theorem ya Pythagoras inasema: $a^2 + b^2 = c^2$, ambapo $a$ na $b$ ni urefu wa pande fupi, na $c$ ni urefu wa hypotenuse (upande mrefu zaidi).

Tuna upande mmoja mfupi $a = 15$ cm, upande mwingine mfupi $b = 8$ cm, na hypotenuse $c = k$.

Jibu la mwisho ni:
$\text{17 cm}$