B. c = ((3)sin45°)/sin40°
Side a is given information: 3cm, and we can find angle A (which is the angle opposite side a) by subtracting the other two angles from 180 because the total interior angle measures of a triangle add to equal 180°.
Angle A = 180 - (95+45) = 40°.
This can be substituted into the equation for the law of sines.
sin(40)°/3 = sin(45)°/c
—Cross multiply
c•sin(40)° = 3•sin(45)°
—divide both sides by sin40 to get the variable c alone and we get:
c = (3)sin(45°)/sin(40°)
this also simplifies to 3.3 cm.
