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4 votes
The area of a rectangle is 20x2 - 27x- 8.
The length is 4x + 1. What is the width?

User Bpedroso
by
4.1k points

2 Answers

2 votes

Answer:

5x-8

Explanation:

im assuming you mean 20x^2 instead of 20x2 bc when you copy and paste it usually gets rid of the "^".

the area of a rectangle is length*width

so, to find the width, we have to solve the equation (4x+1)*width=20x^2-27x-8

the goal is to find (20x^2-27x-8)/(4x+1)

there is many ways to solve this: long division, synthetic division (easiest way)

but I'll just do guess and check

we know that the answer is in the form ax+b

we also know that b*1=-8 bc that's just how foiling works

We also know 4a=20

so, the answer is 5x-8

obviously you can check this answer if you are unsure of it being correct

(4x+1)(5x-8) = 20x^2-32x+5x-8 = 20x^2 - 27x - 8

so it does work

User IneedHelp
by
3.8k points
8 votes

Answer:

5x - 8

Hope it helped :)

User Corrl
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4.1k points