Answer:
D
Step-by-step explanation:
If the original price is x and you deduct 3, you'l have x - 3.
If you buy 4 of them, you multiply that price by 4, giving you 4(x - 3).
Then, if that value is equal to 27, you get 4(x - 3) = 27
Hello :
the solution is : <span>(3, -1)
put x= 3 and y = -1
you have : 3-(-1) = 4 and 3+(-1) = 2 ..... right</span>

Let
, so that
:

Now the ODE is separable, and we have

Integrating both sides gives

For the integral on the left, rewrite the integrand as

Then

and so


Given that
, we find

so that the particular solution to this IVP is

Answer: x = 20.
Step-by-step explanation:
x and (3x + 10) combine to form a right angle, shown in the diagram by the small square joining the perpendicular lines.
Right angles are 90 degrees, so you can add both angles to get 90:
