Answer:
step by step
Step-by-step explanation:
90 degrees is complementary
(4,-3) because that’s where both lines intersect between each other.
Not of Bernoulli type, but still linear.

There's no need to find an integrating factor, since the left hand side already represents a derivative:
![\dfrac{\mathrm d}{\mathrm dx}[(1+x^2)y]=(1+x^2)\dfrac{\mathrm dy}{\mathrm dx}+2xy](https://tex.z-dn.net/?f=%5Cdfrac%7B%5Cmathrm%20d%7D%7B%5Cmathrm%20dx%7D%5B%281%2Bx%5E2%29y%5D%3D%281%2Bx%5E2%29%5Cdfrac%7B%5Cmathrm%20dy%7D%7B%5Cmathrm%20dx%7D%2B2xy)
So, you have
![\dfrac{\mathrm d}{\mathrm dx}[(1+x^2)y]=4x^2](https://tex.z-dn.net/?f=%5Cdfrac%7B%5Cmathrm%20d%7D%7B%5Cmathrm%20dx%7D%5B%281%2Bx%5E2%29y%5D%3D4x%5E2)
and integrating both sides with respect to

yields


Answer: a
Step-by-step explanation:
The function representing the price of the ring x years after 2000 is f(x) = (100 + 35)/100 *x + 590 = 135/100 *x + 590 = 1.35x + 590
i.e. f(x) = 1.35x + 590