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Find all points of intersection of the graphs of the polynomials. f(x)=(x+5)(x-5) and g(x)=(x+1)(x-3)

User Djole
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1 Answer

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Answer:

1 intersection point at (11,96)

Explanation:

Comment

The best way to solve this is to start with a graph. Then you can work out the actual intersection points.

The graph shows that there is only 1 intersect point. Let's try and find it.

Givens

y = (x - 5)(x + 5) = x^2 - 25

y = (x +1)(x - 3) = x^2 -2x - 3

If the intersect points are what you want, then the y value for both equations must be equal.

Solution

x^2 - 25 = x^2 - 2x - 3 Subtract x^2 from both sides

x^2 - x^2 - 25 = x^2 - 2x - 3 Combine

- 25 = - 2x - 3 Add 3 to both sides

-25+3 = -2x - 3 + 3 Combine

-22 = - 2x Divide by - 2

-22/-2 = x

x = 11

y = x^2 - 25

y = 11^2 - 25

y = 121 - 25

y = 96

Find all points of intersection of the graphs of the polynomials. f(x)=(x+5)(x-5) and-example-1
User Desco
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