Math, asked by vagarwal027pcmgu0, 1 year ago

the length and breadth of rectangular garden of Rihanna are 14m and 12m is the cost of constructing an equally white per inside around the garden is rupees 1380 @ rupees 20 per square M then let us read by calculating how much weight is a bath

Answers

Answered by santy2
0

The area of the path is :

1380 / 20 = 69m²

Let width of the path be x then the length of the outer rectangle is :

14 + 2x

Width = 12 + 2x

Area of the path = Area of outer rectangle - Area of inner triangle

Area of outer rectangle :

(2x + 12)(2x + 14) = 4x² + 52x + 168

Area of inner rectangle is :

12 × 14 = 168

4x² + 52x +168 - 168 = 69

4x² + 52x = 69

4x² + 52x - 69 = 0

We will use quadratic formula :

{-52 +/- √52² - 4 × 4 ×-69} / 8

(-52 +/- 61.71) /8

x = 1.21m or - 14.21m

We take the positive value :

x = 1. 21m

Answered by shariquekeyam
0

Step-by-step explanation:

Step-by-step explanation:

The Dimensions of the inner rectangle will be (14 – 2x) × (12 – 2x)

And area of inner rectangular ground = (14 – 2x)(12 – 2x)

Now, area of path = area of the whole garden – an area of the garden without a path

 \frac{cost \: of \: construction}{rate \: of cost \: \: construction}  = \:  168 – 168 + 28x + 24x – 4x2

⇒ \frac{1380}{20}  = 168 – 168 + 28x + 24x – 4x2

⇒ 69 = 168 – 168 + 28x + 24x – 4x2

⇒ 4x2 – 52x + 69 = 0

⇒ 4x2 - 46x – 6x + 69 = 0

⇒ 2x(2x – 23) – 3(2x – 23) = 0

⇒ (2x – 3)(2x – 23) = 0

⇒ 2x – 3 = 0 \:or\: 2x – 23 = 0

⇒ x = 1.5 m \:or\: x = 11.5 m

Now, logically 11.5 m is not possible, because in that case, the length of inner rectangular ground will be negative,

Hence, width of path = x = 1.5 m

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