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The solutions of the equations f(x)= (x+5) (x-2) and g(x)= (2x+7) (x-2) are (-2,12) and (2,0). Show how you get these solutions.

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Answer:

To find the solutions of the equations \(f(x) = (x+5)(x-2)\) and \(g(x) = (2x+7)(x-2)\) and verify that \((-2,12)\) and \((2,0)\) are indeed solutions, you can follow these steps:

1. For \(f(x) = (x+5)(x-2)\):

To find the solutions, set \(f(x)\) equal to zero and solve for \(x\):

\((x+5)(x-2) = 0\)

Now, use the zero-product property, which means that if the product of two factors equals zero, at least one of those factors must be zero:

\((x+5) = 0\) or \((x-2) = 0\)

Solve each equation separately:

\(x+5 = 0\) gives \(x = -5\)

\(x-2 = 0\) gives \(x = 2\)

So, the solutions for \(f(x) = (x+5)(x-2)\) are \(x = -5\) and \(x = 2\).

When you substitute \(x = -2\) into \(f(x)\), you get:

\(f(-2) = (-2+5)(-2-2) = 3*(-4) = -12\)

Therefore, the solution \((-2, 12)\) is confirmed.

2. For \(g(x) = (2x+7)(x-2)\):

Follow the same process. Set \(g(x)\) equal to zero and solve for \(x):

\((2x+7)(x-2) = 0\)

Apply the zero-product property:

\((2x+7) = 0\) or \((x-2) = 0\)

Solve each equation separately:

\(2x+7 = 0\) gives \(2x = -7\), and then \(x = -7/2\)

\(x-2 = 0\) gives \(x = 2\)

So, the solutions for \(g(x) = (2x+7)(x-2)\) are \(x = -7/2\) and \(x = 2\).

When you substitute \(x = 2\) into \(g(x)\), you get:

\(g(2) = (2*2+7)(2-2) = (4+7)(0) = 11*0 = 0\)

Therefore, the solution \((2, 0)\) is confirmed.

These are the solutions for both equations, and they match the given solutions \((-2, 12)\) and \((2, 0)\).

User Pavankumar Vijapur
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