Question

PLEEASEE. No triângulo ABC a seguir, a medida AC’ (x), em cm é igual a:

a. 8 cm.

b. 9 cm.

c. 12 cm.

d. 21 cm.

e. √75 cm.

f. √86 cm.

g. √117 cm.​

Answer 1

$\Large\boxed{\begin{array}{l}\underline{\rm Observe\,o\,anexo.}\\\sf k^2+16^2=20^2\\\sf k^2+256=400\\\sf k^2=400-256\\\sf k^2=144\\\sf k=\sqrt{144}\\\sf k=12\\\sf\dfrac{x}{12}=\dfrac{12}{16}\\\\\sf 16x=12\cdot12\\\sf 16x=144\\\\\sf x=\dfrac{144}{16}\\\\\sf x=9~cm\\\huge\boxed{\boxed{\boxed{\boxed{\sf\maltese~alternativa~b}}}}\end{array}}$