Algebra :please answer #4 and show work

Solve the equation 3x2 + 19x + 9 = 0 to the nearest tenth.

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

Which describes the difference between the graph of f(x)=x^2 and g(x)=-(x^2-2)