Question

A professional interior designer is purchasing wallpaper for two square walls. One wall is 4 feet wider than

the other if 170 square feet of wallpaper is required. What are the wall's measurements?

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Answer 1

Let ones side be a and others be a+4

ATQ

`\\ \sf\longmapsto a^2+(a+4)^2=170`

`\\ \sf\longmapsto a^2+a^2+8a+16=170`

`\\ \sf\longmapsto 2a^2+8a=154`

`\\ \sf\longmapsto a^2+4a=77`

`\\ \sf\longmapsto a^2+4a-77=0`

`\\ \sf\longmapsto a=7\:or\:a=-11`

• a can't be negative

`\\ \sf\longmapsto a=7`

• a+4=7+4=11