The line 2y = 3x + 12 cuts the parabola 4y = 3x2.What is the area encl...
Equation of line 2y = 3x + 12 and equations of parabola 4y=3x
2
= 3 x 4 + 24 - 16 = 36 - 16 = 20 sq. units.
∴Area enclosed by the parabola, the line and the y axis in first quadrant = 20 sq. units
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The line 2y = 3x + 12 cuts the parabola 4y = 3x2.What is the area encl...
Given:
Equation of the line: 2y = 3x - 12
Equation of the parabola: 4y = 3x^2
To find the area enclosed by the parabola, line, and y-axis in the first quadrant, we need to find the points of intersection of the line and the parabola.
Step 1: Find the points of intersection
To find the points of intersection, we can equate the two equations:
3x - 12 = 3x^2/2
Rearranging the terms, we get:
3x^2 - 6x - 24 = 0
Dividing by 3, we get:
x^2 - 2x - 8 = 0
Factoring the quadratic equation, we get:
(x - 4)(x + 2) = 0
So, x = 4 or x = -2
Substituting the values of x back into the equation of the line, we get the corresponding y-values:
For x = 4, 2y = 3(4) - 12
2y = 12 - 12
2y = 0
y = 0
For x = -2, 2y = 3(-2) - 12
2y = -6 - 12
2y = -18
y = -9
Since we are looking for the intersection points in the first quadrant, we discard the point (-2, -9) as it lies in the third quadrant.
Step 2: Find the area enclosed
Now that we have the points of intersection, we can find the area enclosed by calculating the area under the parabola and subtracting the area under the line.
Using integration, we can find the area under the parabola:
∫[0,4] 4y/3 dx = (∫[0,4] 4/3)∫y dx = 4/3 * (∫[0,4] dx)
= 4/3 * [x] [0,4]
= 4/3 * (4 - 0)
= 16/3
Using integration, we can find the area under the line:
∫[0,4] (3x - 12)/2 dy = (∫[0,4] (3x - 12)/2)∫dx = 1/2 * (∫[0,4] 3x - 12) dx
= 1/2 * [(3/2)x^2 - 12x] [0,4]
= 1/2 * [(3/2)(4)^2 - 12(4) - (3/2)(0)^2 - 12(0)]
= 1/2 * [(3/2)(16) - 48 - (3/2)(0) - 0]
= 1/2 * [24 - 48]
= 1/2 * (-24)
= -12
Therefore, the area enclosed by the parabola, line, and y-axis in the first quadrant is:
Area = (16/3) - (-12)
= 16/3 + 12/1
= 64/3 + 36/3
= 100