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Which pair of lines is parallel? a. y=4x+1 and y+4=5 b. y=-2+x and 2y-2x=-2 c. y=1/4x + 2 and y-2=1/2x d. y=1/5x+1 and 5y+x= 10

To find the extreme values of a function f(x. y) on a curve x-x(t), y y(t), treat f as a function of the single variable t and use the chain rule to find where df/dt is zero. in any other single-variable case, the extreme values of f are then found among the values at the critical points (points where df/dt is zero or fails to exist), and endpoints of the parameter domain. find the absolute maximum and minimum values of the following function on the given curves. use the parametric equations x=2cos t, y 2 sin t functions: curves: i) the semicircle x4,y20 i) the quarter circle x2+y-4, x20, y20 b, g(x, y)=xy

How to solve a simultaneous equation involved with fractions?