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16 votes
16 votes
Given the function f(x)=(x+3)^2 and g(x)=3x+13 determine the x values of the point intersection

User Josh Mouch
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1 Answer

11 votes
11 votes

Answer:

x = - 4, x = 1

Explanation:

At the point of intersection

f(x) = g(x) , that is

(x + 3)² = 3x + 13 ← expand left side using FOIL

x² + 6x + 9 = 3x + 13 ( subtract 3x + 13 from both sides )

x² + 3x - 4 = 0 ← in standard form

(x + 4)(x - 1) = 0 ← in factored form

Equate each factor to zero and solve for x

x + 4 = 0 ⇒ x = - 4

x - 1 = 0 ⇒ x = 1

User Paolo Broccardo
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