Respuesta :

caylus

Hi,

cos 60°=x/y=1/2==>2x=y

Pythagore says x²+12²=y²==>144+x²=4x²

==>3x²=144

==>x²=48

==>x=4√3

This triangle is a 30 - 60 - 90 triangle. Unlike in 45 - 45 - 90 triangles, the two legs are not the same. Good news is there's a nice pattern to remember it - and you can check it with the Pythagorean Theorem,

Short leg (opposite 30 degree angle) = 1 unit

Long leg (opposite 60 degree angle) = √3 units

Hypotenuse (opposite 90 degree angle) = 2 units.

If you know one side, the other two can be found by making proportions or scaling up/down. Order is not important - instead knowing the pattern.

We know that the long leg is 12. To go from the long leg to the short leg, we divide by √3. This helps us find x.

x = 12 / √3

= 12 √3 / √3 √3 to rationalize radicals

= 12√3 / 3

= 4√3

To go from the short leg to the hypotenuse, we double the short leg.

2 * 4√3 = 8√3.

Thus, x = 4√3 and y = 8√3.