Henry and irene working together can wash all the windows of their house in 1h 48m. working alone, it takes henry 1.5 h more than irene to do the job. how long does it take each person working alone to wash all the windows?
show equation.

Let the time it takes Irene to do the work alone be x, then
1/x + 1/(x + 1.5) = 1/1.8
1.8(x + 1.5 + x) = x(x + 1.5)
3.6x + 2.7 = x^2 + 1.5x
x^2 - 2.1x - 2.7 = 0
x = 3

Therefore, it takes Irene 3 hours and Henry 4.5 hours to do the work individually.

B. because the 7 represents "seven times", x represents "a number", 12 represents "plus twelve", and -4 represents "minus four"