You have to distribute the 4 to the numbers in the parenthesese. So 4 times 3x which is 12x and 4 times 5 which is 20 so now you get 12x plus 20 equals 8. Now you have to subtract 20 from 8 which is -12 so now you have 12x=-12 now divide the 12 from x and 12 from -12 and so now you have x=-1
Answer:
x = 9
y = 9
Step-by-step explanation:
Given :
Let :
Kenyan French roast coffee = x
Cost per x = $8
Sumatran Coffee = y
Cost per y = $10
x + y = 18 - - - - (1)
8x + 10y = 9 * 18 ;
8x + 10y = 162 - - - - (2)
From (1):
x = 18 - y
Put x = 18 - y in (2)
8(18 - y) + 10y = 162
144 - 8y + 10y = 162
2y = 162 - 144
2y = 18
y = 9
x = 18 - y
x = 18 - 9
x = 9
The one with the steepest slope going down from left to right