PSLE The perimeter of figure CDEFG is (9
w + 22) cm. The perimeter of square CDEF is 16 cm.
- Find the perimeter of triangle CFG in terms of w.
- The perimeter of figure CDEFG is 85 cm. What is the value of w? Give your answer in cm.
(a)
Length of the square
= 16 ÷ 4
= 4 cm
Total lengths of CD, DE and EF
= 3 x 4
= 12 cm
Perimeter of triangle CFG
= 9
w + 22 - 4 - 4
= (9
w + 14) cm
(b)
9
w + 22 = 85
9
w = 85 - 22
9
w = 63
w = 63 ÷ 9 = 7
Value of
w = 7 cm
Answer(s): (a) (9
w + 14) cm; (b) 7 cm