Question

please find attached and answer​

Answer 1

Step-by-step explanation:

We know the formula,

${(a + b + c)}^{2} = {a}^{2} + {b}^{2} + {c}^{2} + 2(ab + bc + ca)$Therefore, by placing the values, we can say,

${12}^{2} = {a}^{2} + {b}^{2} + {c}^{2} \: + 2(12 + 20 + 15) \\ = > 144 = {a}^{2} + {b}^{2} + {c}^{2} + 2(47) \\ = > {a}^{2} + {b}^{2} + {c}^{2} = 144 - 94 \\ = > {a}^{2} + {b}^{2} + {c}^{2} = 50(ans.)$

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