Answer:
Answer is D hope this helps :)
Step-by-step explanation:
Step 1: x²-15=2x
step 2: x²-2x-15=0
step 3: (x-5)(x+3)=0
step 4: x-5=0 or x+3=0
step 5: x=5 of x=-3
Answer:

it must always have one of the sign
Answer:
d/dt(dx/dt)=K(dx/dt)^2
Step-by-step explanation:
Since, a is proportional to v^2; and a=d/dt(dx/dt) and v= dx/dt since they are instantanious acceleration and velocity respectively.
K=(d^x/dt^2)(dt/dx)^2