PSLE The perimeter of figure DEFGH is (7
c + 18) cm. The perimeter of square DEFG is 24 cm.
- Find the perimeter of triangle DGH in terms of c.
- The perimeter of figure DEFGH is 67 cm. What is the value of c? Give your answer in cm.
(a)
Length of the square
= 24 ÷ 4
= 6 cm
Total lengths of DE, EF and FG
= 3 x 6
= 18 cm
Perimeter of triangle DGH
= 7
c + 18 - 6 - 6
= (7
c + 6) cm
(b)
7
c + 18 = 67
7
c = 67 - 18
7
c = 49
c = 49 ÷ 7 = 7
Value of
c = 7 cm
Answer(s): (a) (7
c + 6) cm; (b) 7 cm