1. tentukan keliling persegi dan panjang diagonalnya bila panjang sisinya sebesar √2 cm! 2. tentukan panjang sisi persegi dan diagonalnya jika diketahui kelilin

1) keliling = 4s = 4√2 cm
Diagonal = √(√2^2 + √2^2) = √(2 + 2) = √4 = 2 cm

2) keliling = 12√3
4s = 12√3
s = 12√3/4 = 3√3 cm

Diagonal = √((3√3)^2 + (3√3)^2) = √(27 + 27) = √54 = 3√6 cm

3) keliling = 102
2(p + l) = 102
p + l = 102/2
(8x + 6) + (10x + 27) = 51
18x + 33 = 51
18x = 18
x = 1
Panjang = 8x + 6 = 8(1) + 6 = 14 cm
Lebar = 10x + 27 = 10(1) + 27 = 37 cm

4) keliling = 48
4s = 48
s = 48/4 = 12 cm

Jika yang ditanya nilai x
2(x - 1) = 12
x - 1 = 6
x = 7