Answer:
<em>Rajan must use </em><em>0.75</em><em> liters of 5% hydrochloric acid solution and </em><em>0.25</em><em> liters of 45% hydrochloric acid solution.</em>
Step-by-step explanation:
Let us assume that, x liters of the 5% hydrochloric acid and y liters of the 45% hydrochloric acid solutions are combined.
As Rajan need total of 1 liter of solution, so
i.e
--------------------1
As Rajan needs 5% hydrochloric acid and 45% hydrochloric acid to make a 1 liter batch of 15% hydrochloric acid, hence acid content of the mixture of two acids will be same as of the final one, so

i.e
-------------2
Putting value of x from equation 1 in equation 2,





Putting the value of y in equation 1,

Therefore, Rajan must use 0.75 liters of 5% hydrochloric acid solution and 0.25 liters of 45% hydrochloric acid solution.
Answer:
Graph it on a graphing calculator
Step-by-step explanation:
Answer:
64 cm^2
Step-by-step explanation:
Area of Shaded Region = Area of Parallelogram - Area of Rectangle
Area of Parallelogram = 10 * 7 = 70
Area of Rectangle = 2 * 3 = 6
70 - 6 = 64 cm^2
To do these, start by looking at the "b" value -6.
divide it by 2
-6/2 = -3
now square this number
(-3)^2 = 9
this is what you need for the "c" value
there is only a 5 for the c value so add 4 to both sides of the equation. ( +4 = +4)
y +4 = x^2 -6x +5 +4
y +4 = x^2 -6x +9
y +4 = (x -3)^2
y = (x -3)^2 - 4
vertex ( 3, -4) upwards facing like a bowl, because the "a" value is positive. So the vertex is the minimum, lowest point on the graph.
Answer:
Cooking will be shortest when the househusband covers the beef stew with the heavy lid.
Step-by-step explanation:
The explanation for this is that water boils at 100°C at normal atmospheric pressure & it remains at that temperature until all the water evaporates as steam; the temperature can then go higher in steam form.
So, if he leaves the pan uncovered the pressure above the beef stew will be the atmospheric pressure and the temperature of the stew will not pass the 100°C mark and the food cooks at 100°C.
If he places a light lid on top, the pressure will build up & the temperature at which water remains liquid is a bit higher, but eventually the steam will push the lid to escape thereby releasing pressure & reducing the temperature.
If he puts a heavy lid on the pan the pressure can build up the highest and the temperature of the water in the stew will stay the highest ensuring the fastest cooking.
Basically, the heavier the lid, greater the pressure in the pan. As the pressure gets greater, the saturation temperature at which water starts boiling will be higher. And higher boiling temperatures mean shorter cooking times.