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Help me
Solve this, it's from a worksheet about quadratic equations.

Help me Solve this, it's from a worksheet about quadratic equations.-example-1
User Guru
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1 Answer

4 votes

Answer:

Below

Explanation:

L X W is area of rectangle ...this figure can be viewed as a rectangle on top of a rectangle

top rectangle is 3x-2 wide and (2x+5) - (3x-2) length

area = (3x-2)( (2x+5) - (3x-2) )

= (3x-2) ( -x + 7) = - 3x^2 + 23x -14 units^2

The bottom is then (3x-2 + 2) * (3x-2)

area = (3x)(3x-2) = 9x^2 - 6x units^2

Add the two areas together (-3x^2+23x-14) + (9x^2 -6x)

6x^2 + 17x -14 and this = 25 cm^2 (given)

6x^2 + 17x -14 = 25

6x^2 + 17x - 39 = 0 Use Quadratic Formula to find x = 1.5

then find the longest side using this value of x

3x-2 + 2 = 4.5 cm

2x+5 = 8 cm <=====longest side

User Aaron Blenkush
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