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1. Hi everyone, I realize this problem is probably really simple, but i don't how to get the answer the book asks for. So:

----------------------------------------------------------------------------------
"The graph of the function f(x) = 3x - 4 intersects the x-axis at 4/3 and the y-axis at -4.

i. Let O denote the origin. Find the area of the triangle OAB."

----------------------------------------------------------------------------------

The answers tell me that the answer is (8/3) multiplied by the square root of (x - 4), + 3

How do i get this answer?
2. (Original post by jamieraser)
Hi everyone, I realize this problem is probably really simple, but i don't how to get the answer the book asks for. So:

----------------------------------------------------------------------------------
"The graph of the function f(x) = 3x - 4 intersects the x-axis at 4/3 and the y-axis at -4.

i. Let O denote the origin. Find the area of the triangle OAB."

----------------------------------------------------------------------------------

The answers tell me that the answer is (8/3) multiplied by the square root of (x - 4), + 3

How do i get this answer?
Is A = (4/3; 0) and B = (0; -4)?

If so then it should be [(4/3) * 4] / 2 = 8/3

No idea where that square root come from.
3. (Original post by jamieraser)
Hi everyone, I realize this problem is probably really simple, but i don't how to get the answer the book asks for. So:

----------------------------------------------------------------------------------
"The graph of the function f(x) = 3x - 4 intersects the x-axis at 4/3 and the y-axis at -4.

i. Let O denote the origin. Find the area of the triangle OAB."

----------------------------------------------------------------------------------

The answers tell me that the answer is (8/3) multiplied by the square root of (x - 4), + 3

How do i get this answer?
I am assuming the point (4/3,0) is A and (0,-4) is B

Area of Triangle = 0.5( b x h)
Area of Triangle = 0.5(4/3 x 4)
Area of Triangle = 8/3 or 2.67 3.s.f.
4. (Original post by jamieraser)
Hi everyone, I realize this problem is probably really simple, but i don't how to get the answer the book asks for. So:

----------------------------------------------------------------------------------
"The graph of the function f(x) = 3x - 4 intersects the x-axis at 4/3 and the y-axis at -4.

i. Let O denote the origin. Find the area of the triangle OAB."

----------------------------------------------------------------------------------

The answers tell me that the answer is (8/3) multiplied by the square root of (x - 4), + 3

How do i get this answer?

I don't think you have posted the whole question. The points A and B are not defined, I suspect that these points are needed to find the area of the required triangle.

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Updated: January 21, 2010
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