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Find the points of intersection of the functions y = 4x^2 and y = 2x + 6.

a) (-1, 4) and (6, 9)
b) (3, -9) and (4, 1)
c) (4, -1) and (1, 4)
d) Insufficient information to determine the points of intersection.

1 Answer

2 votes

Final answer:

To find the points of intersection between the functions y = 4x^2 and y = 2x + 6, set the equations equal to each other and solve for x. Using the quadratic formula, we find two possible values for x: 3/2 and -1. Substituting these values into either equation gives the corresponding y values, resulting in the points of intersection (3/2, 9/2) and (-1, 4).

The correct option is A.

Step-by-step explanation:

To find the points of intersection between the functions y = 4x^2 and y = 2x + 6, we need to set the two equations equal to each other and solve for x.

4x^2 = 2x + 6

Next, rearrange the equation to bring all terms to one side:

4x^2 - 2x - 6 = 0

This is a quadratic equation. We can solve for x by factoring or using the quadratic formula.

Using the quadratic formula, we have:

x = (-b ± sqrt(b^2 - 4ac))/(2a)

Plugging in the values a = 4, b = -2, and c = -6, we get:

x = (-(-2) ± sqrt((-2)^2 - 4(4)(-6)))/(2(4))

Simplifying further gives:

x = (-(-2) ± sqrt(4 + 96))/(8)

x = (2 ± sqrt(100))/(8)

x = (2 ± 10)/(8)

x = 12/8 or -8/8

x = 3/2 or -1

Now, substitute the values of x into one of the original equations to find the corresponding y values. Plugging in x = 3/2 into either equation gives:

y = 4(3/2)^2 = 9/2

So, one point of intersection is (3/2, 9/2). Plugging in x = -1 into either equation gives:

y = 4(-1)^2 = 4

So, the other point of intersection is (-1, 4).

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