PSLE The perimeter of figure PQRST is (5
k + 22) cm. The perimeter of square PQRS is 32 cm.
- Find the perimeter of triangle PST in terms of k.
- The perimeter of figure PQRST is 67 cm. What is the value of k? Give your answer in cm.
(a)
Length of the square
= 32 ÷ 4
= 8 cm
Total lengths of PQ, QR and RS
= 3 x 8
= 24 cm
Perimeter of triangle PST
= 5
k + 22 - 8 - 8
= (5
k + 6) cm
(b)
5
k + 22 = 67
5
k = 67 - 22
5
k = 45
k = 45 ÷ 5 = 9
Value of
k = 9 cm
Answer(s): (a) (5
k + 6) cm; (b) 9 cm