Question

Please help show work

Answer 1

`\large\boxed{A.\ (r+5)/((r+7)(r+7)(r-3))}`

Explanation:

`(r+5)/(r^2+5r-14)/(r^2+4r-21)/(r-2)=(r+5)/(r^2+7r-2r-14)\cdot(r-2)/(r^2+4r-21)\\\\=(r+5)/(r(r+7)-2(r+7))\cdot(r-2)/(r^2+7r-3r-21)\\\\=(r+5)/((r+7)(r-2))\cdot(r-2)/(r(r+7)-3(r+7))=(r+5)/((r+7)(r-2))\cdot(r-2)/((r+7)(r-3))\\\\\text{canceled}\ (r-2)\\\\=(r+5)/((r+7))\cdot(1)/((r+7)(r-3))=(r+5)/((r+7)(r+7)(r-3))`