Question

evaluate: (3a - 7b -c)square

Answer 1

Answer:

we will use the formula a+b+c whole square

Step-by-step explanation:

we get

3a^2 + 49b^2+c^2-21ab + 7bc -3ac

Answer 2

ɧɛƖƖơ ɱąɬɛ

Answer:

9a² +49b² +c²-42ab+14bc-6ac

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Step-by-step explanation:

Qᴜᴇsᴛɪᴏɴ:

ᴇᴠᴀʟᴜᴀᴛᴇ: (3a - 7b -c)²

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Sᴏʟᴜᴛɪᴏɴ:

ᴡᴇ ᴋɴᴏᴡ ᴛʜᴀᴛ ,

(a – b – c)² = a² + b² + c² – 2ab + 2bc – 2ca

sᴏ, ʙʏ ᴜsɪɴɢ ᴛʜᴇ ᴀʙᴏᴠᴇ ɪᴅᴇɴᴛɪᴛʏ,

→(3a - 7b -c)²= (3a)²+(7b)²+(c)²-2(3a)(7b) + 2(7b)(c) -2(c)(3a)

→(3a - 7b -c)² =9a² +49b² +c²-2(21ab)+2(7bc)-2(3ac)

→(3a - 7b -c)² =9a² +49b² +c²-42ab+14bc-6ac

ʜᴇɴᴄᴇ ᴛʜᴇ ᴀɴsᴡᴇʀ ɪs : 9a² +49b² +c²-42ab + 14bc - 6ac

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