Good afternoon, my children. u ^ u

Solve the equation x/4 - 5= -8 -27 -12 -7 12

Y+ 2/y is it a polynomial in one variable or not? and if so, why?

How many liters of peroxide should be added to 12 liters of an 8% peroxide solution so that the resulting solution contains 16% peroxide?   original added new amount of peroxide 0.96 liters x 0.96 + x amount of solution 12 liters x 12 + x 0.18 liter 1.14 liters 1.92 liters 2.10 liters