Question

`factorise \: \\ \\ r {}^(2) - 10r + 21`
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Answer 1

`\implies {\blue {\boxed {\boxed {\purple {\sf { \: (r - 7)(r - 3) }}}}}}`

`\sf \bf {\boxed {\mathbb {STEP-BY-STEP\:\:EXPLANATION:}}}`

`{r}^(2) - 10r + 21`

`= {r}^(2) - 7r - 3r + 21`

Taking
`r` as common from first two terms and
`3` from last two terms, we have

`= r(r - 7) - 3(r - 7)`

Taking the factor
`(x-7)` as common,

`= (r - 7)(r - 3)`

`\bold{ \green{ \star{ \orange{Mystique35}}}}⋆`

Answer 2

Explanation:

Your Answer with

Explanation is given in the attachment

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