How many times does the graph of 4x = 32 - x2 cross the x-axis ?
2 answers:
Answer:
Step-by-step explanation:
● 4x = 32 - x^2
Add x^2 to both sides
● 4x +x^2 = 32 -x^2+x^2
● x^2 +4x = 32
Substract 32 from both sides
● x^2+4x -32 =32-32
● x^2 +4x-32=0
That is a quadratic equation
We will use the determinant method
The determinant is b^2-4ac
● a = 1
● b = 4
● c = 32
● b^2-4ac = 4^2 -4×1×(-32) = 144
144 is positive so the parabola will cross the x-axis two times
● x = (-b -/+ √(b^2-4ac))/2a
● x = (-4 +/- 12) /2
● x = 8/2 or x= -16/2
● x = 4 or x =-8
The solutions are 4 and -8
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Given, the density of a particular brand of gasoline = 0.737 g/ml.
13.4 gallon of tank given. We have to find the mass of gasoline to fill the tank.
First we will convert 13.4 gallon to ml.
We know that 1 gallon = 3.78541 litre
And 1 litre = 1000 ml
So we can write 1 gallon = = 3785.41 ml.
13.4 gallon = ml = 50724.494 ml.
Let's take there is x grams of gasoline
We know that density = (mass/ volume) =
So we can write,
To find x we will multiply both sides by 50724.494. we will get,
So we have got the required answer.
Mass of gasoline = 37383.95 grams.