If x+2 is a factor of the polynomial: 3x²+kx, then the value is​

k = 6

Step-by-step explanation:

(x+2) is a factor of 3x²+kx so if we solve (x+2) = 0 that will give us one of the solutions of x for 3x²+kx = 0, and then we can substitute that solution in and find the value of k.

So to find a solution, (x+2) = 0 and therefore x = -2

Now substitute x = -2 into 3x²+kx = 0

so 3(-2)²+k(-2) = 0

12 - 2k = 0

2k = 12

k = 6

answer is 8x+24

area of vanessa's patio = length × width

given, length = (3x² + 5x + 10)

width = (x² - 3x - 1)

area of vanessa's patio = (3x² + 5x + 10)(x² - 3x - 1)

= 3x²(x² - 3x - 1) + 5x(x² - 3x - 1) + 10(x² - 3x - 1)

= 3x⁴ - 9x³ - 3x² + 5x³ - 15x² - 5x + 10x² - 30x - 10

= 3x⁴ - 4x³ - 8x² - 35x - 10

hence, expression of vanessa's patio = (3x⁴ - 4x³ - 8x² - 35x - 10)