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spndsh
describe the domain of g(x,y)= 3x +5y/(x^2 +y^2-9)
Domain = all POSSIBLE numbers. With that being said, you cannot divide by 0. Therefore whatever x and y values that make the denominator = zero are NOT in the domain. Set x^2+y^2-9 equal to zero and solve. Since there are two variables you must must solve for y first and then subsitute that in for y.
i got x= (7)^1/2 & y=.125
I havent dont the math but if those two numbers make the denominator zero. the domain is x cannot equal (7)^1/2 & y=.125