Cos a+cosb+cosc=1+4sina/2*sinb/2*sinc/2

What is a rational number between 9.5 and 9.7

Which of these equations, when solved, gives a different value of x than the other three? a9.1 = -0.2x + 10 b10 = 9.1 + 0.2x c10 – 0.2x = 9.1 d9.1 – 10 = 0.2x

Solve each quadratic equation by factoring and using the zero product property. n^2 - 49 = 0