The measures of angles A, B and C of a triangle are in the ratio 3:4:5. What is the measure, in degrees, of the largest angle?	Choose the most appropriate option:  A) 35°  B) 65°  C) 85°  D) 75°  E) 55°
Let the sizes of angles A, B and C be written as follows   A = 3 x, B = 4 x and C = 5 x , where x is a common factor.   The sum of all three angles is equal to 180°. hence   3 x + 4 x + 5 x = 180°   Solve the above equation for x   x = 15   The size of the largest angle is equal to   5 x = 5 * 15= 
<gadget id="calculator">5 * 15</gadget>
<output>75</output>
75°   correct answer 75°
<result>D</result>
The measures of angles A, B and C of a triangle are in the ratio 3:4:5. What is the measure, in degrees, of the largest angle?