Ken can paint a room in 5 hours, and barbie can paint it in 4 hours. how long will it take if they work together?

Use the x-intercept method to find all real solutions of the equation. -9x^3-7x^2-96x+36=3x^3+x^2-3x+8

Use the quadratic formula to solve the equation. if necessary, round to the nearest hundredth. x^2 - 20 = x a. 5, 4 b. -5, -4 c. -5, 4 d. 5, -4

Use the elimination method to solve the systems of equations.choose the correct ordered pair. 7x+4y=39