Atank can hold 50 liters of water. at present, it is only 30% full. how many liters of water shall i put in the tank, so that is it 50% full?

Calculate how many liters you need to be half full:

50 liters x 50% = 50 x 0.5 = 25 liters to be half filled.

Calculate how many liters are in the tank now:

50 x 0.30 = 15 liters

Now subtract to find how many more liters are needed:

25 - 15 = 10 more liters.

x=-2

infinite number of lines, so there is an infinite number of equations.

step-by-step explanation:

there are an infinite number of line that passes through the point (-2,5)

x=-2   is one line that passes through the point

y = 5 is another line that passes through the point

(these two lines are perpendicular to each other).

since the number of   numbers are infinite and the slope is the ratio of two numbers,(change in y over change in x) we can have an infinite number of slopes.     our only condition is that it passes through the point (-2,5)

y = 5x + 17

step-by-step explanation:

a perpendicular line will be the opposite reciprocal slope of the given equation.   the slope given is -1/5 so the opposite reciprocal is 5

find b:

7 = 5 (-2) + b

7 = -10 + b

17 = b

write equation

y = 5x + 17