PSLE The perimeter of figure VWXYZ is (7
w + 15) cm. The perimeter of square VWXY is 20 cm.
- Find the perimeter of triangle VYZ in terms of w.
- The perimeter of figure VWXYZ is 78 cm. What is the value of w? Give your answer in cm.
(a)
Length of the square
= 20 ÷ 4
= 5 cm
Total lengths of VW, WX and XY
= 3 x 5
= 15 cm
Perimeter of triangle VYZ
= 7
w + 15 - 5 - 5
= (7
w + 5) cm
(b)
7
w + 15 = 78
7
w = 78 - 15
7
w = 63
w = 63 ÷ 7 = 9
Value of
w = 9 cm
Answer(s): (a) (7
w + 5) cm; (b) 9 cm