INFORMATION:
We have the following expression
![c^2-8c+16-4d^2](https://img.qammunity.org/2023/formulas/mathematics/college/cba9dpu8ivckoju8m3uae47zuznekd7nd9.png)
And we must factor it by grouping
STEP BY STEP EXPLANATION:
To factor it by grouping, we must:
1. group the first 3 terms of the expression
![(c^2-8c+16)-4d^2](https://img.qammunity.org/2023/formulas/mathematics/college/lshhv3dnsji2h285z958p4owzyumg6d4cy.png)
2. factor the expression in the parenthesis
![(c-4)^2-4d^2](https://img.qammunity.org/2023/formulas/mathematics/college/fyzz2knhzrzhy6h46esvi3sygijgppyykr.png)
3. rewrite 4d^2 as unique exponential expression
![(c-4)^2-(2d)^2](https://img.qammunity.org/2023/formulas/mathematics/college/kiswegrulny7n5ergb3l2dci6wjq3or3to.png)
4. factor by square difference
![((c-4)+2d)((c-4)-2d)](https://img.qammunity.org/2023/formulas/mathematics/college/565pjkzlwzwc63lz9xf0g8cttnepdluzx8.png)
5. simplify
![=(c+2d-4)(c-2d-4)](https://img.qammunity.org/2023/formulas/mathematics/college/iqy07ef9tfck3t6w7yo6nf7qvdaopc70x6.png)
ANSWER:
the factoring for c^2-8c +16 -4d^2 by grouping is
![(c+2d-4)(c-2d-4)](https://img.qammunity.org/2023/formulas/mathematics/college/rcl2sc4td5k0cla124wy55gnx9089udvp0.png)