Question

The dimensions of a rectangle can be given by x + 4 and x - 3. If the area of the rectangle is 30 meters. Find it's dimensions.

Answer 1

Explanation:

Dimension of rectangle is x+4 and x-3

let's , suppose x+4 is lenght and x-3 is breadth

perimeter of rectangle = L×B

∵ L×B = (x+4)×(x-3) = 30

=>x²-3x + 4x -12 = 30

=>x²+x = 30+12

=>x²+x -42 =0

=>x²+x - 42 = 0

=>x²+7x-6x -42 = 0

=>x(x+7)-6(x+7)

=>(x+7)(x-6 )

• x= -7 or 6

neglect negative term ( -7)

so,length x+4 = 6+4 = 10

breadth ,x-3 = 6-3 = 3

dimension of the rectangle is 10, 3

Answer 2

6 x 5

Explanation:

Start by setting (x+4)(x-3) = 30

x^2 - 3x + 4x - 12 = 30

x^2 + x - 42 = 0

(x-6)(x+7) = 0

Solution for x is [6]

length x width = 30

6 x (width) = 30

6 x (5) = 30

{6,5}