PSLE The perimeter of figure JKLMN is (9
j + 25) cm. The perimeter of square JKLM is 12 cm.
- Find the perimeter of triangle JMN in terms of j.
- The perimeter of figure JKLMN is 88 cm. What is the value of j? Give your answer in cm.
(a)
Length of the square
= 12 ÷ 4
= 3 cm
Total lengths of JK, KL and LM
= 3 x 3
= 9 cm
Perimeter of triangle JMN
= 9
j + 25 - 3 - 3
= (9
j + 19) cm
(b)
9
j + 25 = 88
9
j = 88 - 25
9
j = 63
j = 63 ÷ 9 = 7
Value of
j = 7 cm
Answer(s): (a) (9
j + 19) cm; (b) 7 cm