-3x + y = 7
-4x + 4y =-12

Step-by-step explanation:

multiplying eq 1 by 4and eq 2 by 3 ,we get

-12x+4y=28

-12x+12y=-36

solving eq 1and 2

4y-12y=64

-8y=64

y=-8

x=-5

answer: y = -2.5x - 15

              (-6,0)

step-by-step explanation:

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)