Using the trigonometric ratio of sine for the angle 40 in the right triangle, w is equal to 18cm approximately to the nearest whole centimeters.
The trigonometric ratios is concerned with the relationship of an angle of a right-angled triangle to ratios of two side lengths.
The basic trigonometric ratios includes;
sine, cosine and tangent.
sin 40° = w/28 cm {opposite/hypotenuse}
w = 28 cm × sin 40° {cross multiplication}
w = 17.9980 cm.
Therefore, the length of side w is derived to be equal to 18 cm approximately to the nearest whole centimeters.