Mathematics
Give possible expressions for the length and breadth of each of the following rectangles, in which their areas are given:
(i) Area: 25a2 - 35a + 12
(ii) Area: 35y2 + 13y - 12
Answer
(i) 25a2 - 35a + 12
Area of Rectangle = Length x Breadth
= 25a2 - 35a + 12
= 25a2 -(20a + 15a) + 12
= 25a2 -20a -15a + 12
= 5a(5a - 4) - 3(5a - 4)
= (5a - 4)(5a - 3)
Hence, one possible answer is : Length = 5a - 3, Breadth = 5a - 4
(ii) 35y2 + 13y - 12
Area of Rectangle = Length x Breadth
= 35y2 + 13y - 12
= 35y2 +(28y - 15y) - 12
= 35y2 + 28y - 15y - 12
= 7y(5y + 4) - 3(5y + 4)
= (5y + 4)(7y - 3)
Hence, one possible answer is : Length = 7y - 3, Breadth = 5y + 4
Related Questions
If x + y + z = 0, show that x3 + y3 + z3 = 3xyz
Without actually calculating the cubes, find the value of each of the following:
(i) (-12)3 + (7)3 + (5)3
(ii) (28)3 + (-15)3 + (-13)3
What are the possible expressions for the dimensions of the cuboids whose volume are given below?
(i) Volume: 3x2 - 12x
(ii) Volume: 12ky2 + 8ky - 20k