Question

Tʜᴇ ᴛᴡᴏ sɪᴅᴇs ᴏғ ᴀ ᴛʀɪᴀɴɢᴜʟᴀʀ ғʟᴀɢ ᴀʀᴇ 30 ᴄᴍ ᴀɴᴅ 40 ᴄᴍ. Fɪɴᴅ ᴛʜᴇ ʟᴇɴɢᴛʜ ᴏғ ᴛʜᴇ ᴛʜɪʀᴅ sɪᴅᴇ ɪғ ᴛʜᴇ ᴘᴇʀɪᴍᴇᴛᴇʀ ᴏғ ᴛʜᴇ ғʟᴀɢ ɪs 130 ᴄᴍ ?​

Answer 1

Given:

The two sides of a triangular flag are 30 cm and 40 cm. & the perimeter of triangular flag is 130 cm.

• Need to find: The third side?

⠀⠀━━━━━━━━━━━━━━━━━━━━━━━━━━━━━⠀⠀

❍ Let's Consider the third side of triangular flag be x cm.

As we know that,

❝Perimeter of the triangle is Given by Sum of its all three sides i.e ( P ) = a + b + c.❞

Therefore:

$\qquad\star\:\underline{\boxed{\pmb{\sf{Perimeter_{\;(triangle)} = a + b + c}}}}$

where,

a, b and c are the three sides of the triangle.

& the Perimeter is Given that is 130 cm

⠀⠀

⠀⠀⠀$\underline{\bf{\dag} \:\mathfrak{Substituting\;the\:values\: :}}$⠀⠀⠀⠀

$:\implies\sf Perimeter_{\;(triangle)} = a + b + c \\\\\\:\implies\sf 30 + 40 + x=130\\\\\\:\implies\sf 130 = 70 + x=130\\\\\\:\implies\sf x = 130 - 70\\\\\\:\implies\underline{\boxed{\pmb{\frak{\purple{x = 60}}}}}\;\bigstar$

$\therefore{\underline{\textsf{Hence, the third side of the triangular flag is \textbf{60 cm}.}}}$