Find the vertex of y=x2−10x+21y = x^2 - 10x + 21y=x2−10x+21.A(5,4)(5, 4)(5,4)B(−5,−4)(-5, -4)(−5,−4)C(5,−4)(5, -4)(5,−4)check_circleD(10,21)(10, 21)(10,21)Explanationx=10/2=5x = 10/2 = 5x=10/2=5, y(5)=25−50+21=−4y(5) = 25 - 50 + 21 = -4y(5)=25−50+21=−4.