PSLE The perimeter of figure ABCDE is (9
p + 17) cm. The perimeter of square ABCD is 12 cm.
- Find the perimeter of triangle ADE in terms of p.
- The perimeter of figure ABCDE is 80 cm. What is the value of p? Give your answer in cm.
(a)
Length of the square
= 12 ÷ 4
= 3 cm
Total lengths of AB, BC and CD
= 3 x 3
= 9 cm
Perimeter of triangle ADE
= 9
p + 17 - 3 - 3
= (9
p + 11) cm
(b)
9
p + 17 = 80
9
p = 80 - 17
9
p = 63
p = 63 ÷ 9 = 7
Value of
p = 7 cm
Answer(s): (a) (9
p + 11) cm; (b) 7 cm