PSLE The perimeter of figure RSTUV is (5
r + 22) cm. The perimeter of square RSTU is 20 cm.
- Find the perimeter of triangle RUV in terms of r.
- The perimeter of figure RSTUV is 67 cm. What is the value of r? Give your answer in cm.
(a)
Length of the square
= 20 ÷ 4
= 5 cm
Total lengths of RS, ST and TU
= 3 x 5
= 15 cm
Perimeter of triangle RUV
= 5
r + 22 - 5 - 5
= (5
r + 12) cm
(b)
5
r + 22 = 67
5
r = 67 - 22
5
r = 45
r = 45 ÷ 5 = 9
Value of
r = 9 cm
Answer(s): (a) (5
r + 12) cm; (b) 9 cm