Which of the following could be an example of a function with a range (-∞,a] and a domain [b, ∞) where a > 0 and b > 0?
a. ƒ(x)= √(x-a)+b
b. ƒ(x)=-√(x-b)+a
c. ƒ(x)=-3√(x+a)-b
d. ƒ(x)=3√(x+b)-a

John used linear combination to solve the system of equations shown. he did so by multiplying the first equation by -3 and the second equation by another number to eliminate the x-terms. what number did jonas multiply the second equation by? 4x-6y=23x+5y=11