PSLE The perimeter of figure JKLMN is (5
v + 20) cm. The perimeter of square JKLM is 28 cm.
- Find the perimeter of triangle JMN in terms of v.
- The perimeter of figure JKLMN is 60 cm. What is the value of v? Give your answer in cm.
(a)
Length of the square
= 28 ÷ 4
= 7 cm
Total lengths of JK, KL and LM
= 3 x 7
= 21 cm
Perimeter of triangle JMN
= 5
v + 20 - 7 - 7
= (5
v + 6) cm
(b)
5
v + 20 = 60
5
v = 60 - 20
5
v = 40
v = 40 ÷ 5 = 8
Value of
v = 8 cm
Answer(s): (a) (5
v + 6) cm; (b) 8 cm