PSLE The perimeter of figure BCDEF is (6
x + 22) cm. The perimeter of square BCDE is 24 cm.
- Find the perimeter of triangle BEF in terms of x.
- The perimeter of figure BCDEF is 76 cm. What is the value of x? Give your answer in cm.
(a)
Length of the square
= 24 ÷ 4
= 6 cm
Total lengths of BC, CD and DE
= 3 x 6
= 18 cm
Perimeter of triangle BEF
= 6
x + 22 - 6 - 6
= (6
x + 10) cm
(b)
6
x + 22 = 76
6
x = 76 - 22
6
x = 54
x = 54 ÷ 6 = 9
Value of
x = 9 cm
Answer(s): (a) (6
x + 10) cm; (b) 9 cm