Pls help! how many solutions does this equation have?
a ) no solution
b ) exactly one solution
c ) exactly two solutions
d ) infinitely many solutions

Two numbers have a sum of -19. one number is x. what expression represents the other number?

If f(x) = 4x - 3 and g(x) = x + 4, find (f - g) (x)

The diameter of the moon is about 3500 km. approximate the surface area of the moon using the formula for the surface area of a sphere, s = 4? r^2. write your answer in scientific notation.