Write the expression 5x+4x^2(2x+7)-6x^2-9x as a polynomial in standard form

8x^3 + 22x^2 - 4x

Step-by-step explanation:

5x+4x^2(2x+7)-6x^2-9x

Open the bracket

5x + 8x^3 + 28x^2 - 6x^2 - 9x

= 8x^3 + 28x^2 - 6x^2 - 9x + 5x

= 8x^3 + 22x^2 - 4x

In standard form, the polynomial 5x+4x^2(2x+7)-6x^2-9x is 8x^3 + 22x^2 - 4x

d) 30 units^2

area of rectangle = l × b

we know,

length = 10 unit

breadth = 3 unit

applying the formula,

= l × b

= 10 × 3

= 30 unit^2

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