SOLUTION: The area of a rectang;e is 70. If the length is one less than 3 times the width,find the length and the width.

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Question 355718: The area of a rectang;e is 70. If the length is one less than 3 times the width,find the length and the width.
Answer by ewatrrr(24785) About Me  (Show Source):
You can put this solution on YOUR website!
Hi,
*Note: Area is length * width
.
let x be the width. then (3x-1) would be the length
.
question states
x(3x-1) = 70
.
3x%5E2+-x+-+70+=+0
.
solve using the quadratic formula
x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+
.
x+=+%281+%2B-+sqrt%28+841+%29%29%2F%286%29+
.
x+=+%281+%2B-+29%29%2F%286%29+
x = 5 and
x = -28/6 = -14/3 = -4.667