Application of Rational Equations

Katherine can paint a room in 4 hours. Joe needs 6 hours to paint the same room. Which equation would you use to determine how long it takes them to paint the room if they work together?

Solve by using the LCD.

George can build a laptop twice as fast as Kurt. Working together, it takes them 3 hours. Which equation would you use to determine how long it will take Kurt working alone?

Solve

• k = 1,  k = 5

• k = −1,  k = 5

• k = −1,  k = −3

• k = 1

• n=-2

• {n= -2,12}

• No solution

• {n= 2,12}

• {c= -6,8}

• c= 4

• c=8

• no solution

• r= -5

• r=2

• r=-2

• no solution

• y=-5/3

• y=4

• {y=-5/3,4}

• No Solution

Solve for x

• 5/3, 1

• - 5, 1

• 5, 2/3

• 5, 1

• a= -3

• a= -4

• a =12

• {a= -3,4}