PSLE The perimeter of figure GHJKL is (9
a + 21) cm. The perimeter of square GHJK is 12 cm.
- Find the perimeter of triangle GKL in terms of a.
- The perimeter of figure GHJKL is 66 cm. What is the value of a? Give your answer in cm.
(a)
Length of the square
= 12 ÷ 4
= 3 cm
Total lengths of GH, HJ and JK
= 3 x 3
= 9 cm
Perimeter of triangle GKL
= 9
a + 21 - 3 - 3
= (9
a + 15) cm
(b)
9
a + 21 = 66
9
a = 66 - 21
9
a = 45
a = 45 ÷ 9 = 5
Value of
a = 5 cm
Answer(s): (a) (9
a + 15) cm; (b) 5 cm