Question

find x if 12 , x, 3 are in proportion​

Answer 1

Answer:

Answer : Since 3,x,12 are in continued-proportion, 3,x,x,12 are in proportion. ⇒ x =.

6.20

Answer 2

$12 \: : x = x\ : 3$

$\frac{12}{x} = \frac{x}{3}$

$12 \times 3 = {x}^{2}$

$36 = {x}^{2}$

${x}^{2} = 36$

$x = \sqrt{36}$

$x = 6$