Answer:
#1: 11 cm
#2: 16.5 in
#3: 2.5 feet
Explanation:
#1
Solve for width by substracting 2l on both sides to isolate 2w
![P-2l=2w](https://img.qammunity.org/2021/formulas/mathematics/high-school/9kiul0x34x36parkaex3olkr995r6qv2nk.png)
or
![2w=P-2l](https://img.qammunity.org/2021/formulas/mathematics/high-school/r96of48uap3ssfxw7ecbtc29edl2b2iib7.png)
Replace.
![2w=26-2(2)\\2w=26-4\\2w=22\\w=(22)/(2)\\ w=11cm](https://img.qammunity.org/2021/formulas/mathematics/high-school/h6v82i58uqcmmby1r91nrxf6sf8b6wva7p.png)
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#2
![P=2l+2w](https://img.qammunity.org/2021/formulas/mathematics/middle-school/etogfgv8l3noodrpi9g5odp43pg0p9l5i8.png)
![P=2(3.5)+2(4.75)\\P =7+9.5\\P=16.5in](https://img.qammunity.org/2021/formulas/mathematics/high-school/efnuzqhpzes50c6xipmzcv1pmthyii76rj.png)
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#3
![P=2l+2w](https://img.qammunity.org/2021/formulas/mathematics/middle-school/etogfgv8l3noodrpi9g5odp43pg0p9l5i8.png)
Solve for l
![2l=P-2w\\2l=7-2(1)\\2l=7-2\\2l=5\\l=(5)/(2)\\ l=2.5feet](https://img.qammunity.org/2021/formulas/mathematics/high-school/b6i87qrvdzzwva02z03cwnjhfd0e2akpf8.png)