Question

1.Find the perimeter of rectangle whose dimensions are 5x –y and 2 (x +y) 2.Say the value of the polynomial m3 + n3 + p3 – 3 mnp at m = 1, n = -1 and p = 2​

Answer 1

ANSWER 1:)

Given:

• Dimensions of rectangle = (5x - y), 2(x + y)

To Find:

• Perimeter of the rectangle

Solution:

We are given that,

⇒ Dimensions of the rectangle = (5x - y) & 2(x + y)

⇒ Dimensions of the rectangle = (5x - y) & (2x + 2y)

We know that,

⇒ Perimeter of rectangle = 2(l + b)

So,

⇒ Perimeter of the rectangle = 2[(5x - y) + (2x + 2y)]

⇒ Perimeter of the rectangle = 2(5x - y + 2x + 2y)

⇒ Perimeter of the rectangle = 2(7x + y)

Therefore,

⇒ Perimeter of the rectangle = 14x + 2y

ANSWER 2:)

Given:

• m³ + n³ + p³ - 3mnp

To Find:

• Value at m = 1, n = -1, and p = 2

Solution:

We are given that,

⇒ m³ + n³ + p³ - 3mnp

But, we need to find the value at m = 1, n = -1, and p = 2.

So,

⇒ m³ + n³ + p³ - 3mnp

⇒ (1)³ + (-1)³ + (2)³ - 3(1)(-1)(2)

⇒ 1 + (-1) + 8 - (-6)

⇒ 1 - 1 + 8 + 6

⇒ 14

Hence,

⇒ m³ + n³ + p³ - 3mnp = 14