The sides of a triangle are 14 cm, 48 cm and 50 cm. The perpendicular distance from the longest side to the midpoint of the shortest side is, in cm? (perpendicular to longest side)
We want to find x .
First let's find cos a using the law of cosines: c2 = a2 + b2 - 2ab cos C
482 = 142 + 502 - 2(14)(50) cos a
2304 = 196 + 2500 - 1400 cos a
-392 = -1400 cos a
0.28 = cos a
And using the Pythagorean identity
0.282 + sin2 a = 1
sin2 a = 0.9216
sin a = 0.96
Now....let's just look at the little triangle.
sin a = opposite / hypotenuse
sin a = x / 7
0.96 = x / 7
7 * 0.96 = x
6.72 = x
We want to find x .
First let's find cos a using the law of cosines: c2 = a2 + b2 - 2ab cos C
482 = 142 + 502 - 2(14)(50) cos a
2304 = 196 + 2500 - 1400 cos a
-392 = -1400 cos a
0.28 = cos a
And using the Pythagorean identity
0.282 + sin2 a = 1
sin2 a = 0.9216
sin a = 0.96
Now....let's just look at the little triangle.
sin a = opposite / hypotenuse
sin a = x / 7
0.96 = x / 7
7 * 0.96 = x
6.72 = x