PSLE The perimeter of figure PQRST is (9
b + 14) cm. The perimeter of square PQRS is 12 cm.
- Find the perimeter of triangle PST in terms of b.
- The perimeter of figure PQRST is 50 cm. What is the value of b? Give your answer in cm.
(a)
Length of the square
= 12 ÷ 4
= 3 cm
Total lengths of PQ, QR and RS
= 3 x 3
= 9 cm
Perimeter of triangle PST
= 9
b + 14 - 3 - 3
= (9
b + 8) cm
(b)
9
b + 14 = 50
9
b = 50 - 14
9
b = 36
b = 36 ÷ 9 = 4
Value of
b = 4 cm
Answer(s): (a) (9
b + 8) cm; (b) 4 cm