Multiple choice

In an isosceles triangle, two equal sides are each 8 cm less than three times the third side. The perimeter of triangle is 33 cm. What is the measurement of equal sides?

  1. 7 cm

  2. 8.2 cm

  3. 13 cm

  4. 5 cm


Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Let the third side is = x 

 Three times of x is = 3x  8 cm less than 3 times = ( 3x - 8 ) cm  two equal sides are = ( 3x - 8 ) cm Perimeter of of triangle is sum of all sides                   ( 3x - 8 ) + ( 3x -  8 ) + x = 33                     3x - 8 + 3x - 8 + x = 33                                        3x + 3x + x - 8 - 8 = 33                                         7x - 16 = 33                                             7x = 33 + 16                                           7x = 49                              x = 49 / 7                                         x = 7 cm                        Third side is 7 cm                    Two equal sides are =( 3 x 7 ) - 8                                               = 21 - 8                                                = 13 cm                                                    Two equal sides measure = 13 cm each