PSLE The perimeter of figure CDEFG is (10
j + 23) cm. The perimeter of square CDEF is 12 cm.
- Find the perimeter of triangle CFG in terms of j.
- The perimeter of figure CDEFG is 83 cm. What is the value of j? Give your answer in cm.
(a)
Length of the square
= 12 ÷ 4
= 3 cm
Total lengths of CD, DE and EF
= 3 x 3
= 9 cm
Perimeter of triangle CFG
= 10
j + 23 - 3 - 3
= (10
j + 17) cm
(b)
10
j + 23 = 83
10
j = 83 - 23
10
j = 60
j = 60 ÷ 10 = 6
Value of
j = 6 cm
Answer(s): (a) (10
j + 17) cm; (b) 6 cm