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URGENT!! The function f(x) = 3x² + kx + 8 has one intersection with the line g(x) = -4x + 5. Determine the value of k that makes this true.

User Gigelsmith
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Answer:-4 or 8

Step-by-step explanation:The line g(x) = -4x + 5 and the function f(x) = 3x2 + kx + 8 cross at one point. By setting f(x) equal to g(x) and solving for x, we can determine the value of k that makes this true.

3x² + kx + 8 = -4x + 5....... (i)

3x² + (k+4)x + 3 = 0....... (ii)

Given that there is only one crossing point, the quadratic equation's discriminant must be zero.

(k+4)² - 4(3)(3) = 0.... (iii)

k² + 8k - 32 = 0...... (iv)

(k+4)(k-8) = 0....... (v)

k = -4 or k = 8

As a result, either -4 or 8 is the value of k that makes the assertion true.

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