Question

please give me answer ​

Answer 1

As length are in the ratio 3:2:5 and have perimeter 30cm ....We could write it as

3x+2x+5x=30 ..Solving this we get. x=3

As 5x is the longest side we will write it as

5x = 5×3 = 15 cm

Answer 2

Answer:

$let \: side \: (1) \: be \: 3x \\ let \: side \: (2) \: be \: 2x \\ let \: side \: (3) \: be \: 5x \\ perimeter \: of \: triangle \: = \: side \: + \: side \: + \: side \\ 30cm \: = \: 3x + 2x + 5x \\ 30cm \: = \: 10x \\ x \: = \: \frac{30}{10} \: = \: 3 \\ therefore \\ side \: (1) = 3 \times 3 = 9cm \\ side \: (2) = 3 \times 2 = 6cm \\ side \: (3) = 3 \times 5 = 15cm \\ \\ therefore \: the \: longest \: side \: is \: 15cm$