Answer:
D) Only (-1,9) is a solution.
Step-by-step explanation:
x+y =8
x^2 + y = 10
Lets check the first point (-1,9)
Put in x =-1 y =9
x+y =8
-1+9 = 8
8 =8
This works
x^2 + y = 10
(-1)^2 +9 =10
1+9 = 10
10 = 10
This works
Lets check the second point (-2,6)
Put in x =-2 y =6
x+y =8
-2+6 = 8
4=8
This does not work
We can stop now. (-2,6) cannot be a solution
6x-21>3
Add 21 to both sides
6x>24
Divide 6 on both sides
X>4
14x+11>-17
Subtract 11 from both sides
14x>-28
Divide 14 on both sides
X<-2
It depends if its decreasing 25% of the original quantity or decreasing by 25% of the quanity that is after already increasing by 25%.