Answer:
Step-by-step explanation:
First, we will eliminate the x, so we multiply the first one by 2.
4x+6y=4
4x-2y=4
So, we have y=0, and we put that in the equations, so x is 1
D(t) = -4t^3 + 40t^2 + 500t = 4088
4t^3 - 40t^2 - 500t + 4088 = 0
t = 7
Therefore, the plane has flown 4088 km 7 hours after it took off.
Answer:
they are 16 and 4
Step-by-step explanation:
We can call the numbers x and y and we can write:
x - y = 12
x + y = 20
Adding these equations gives us 2x = 32 which means x = 16 and substituting this value into the first equation gives us y = 4.
You just multiply the x value by 5
-2(5)=-10
-1(5)=-5
0(5)=0
3(5)=15
6(5)=30
9(5)=45