# Pre Calculus

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Determine the coordinates of the point (xy) where the curves y=(12)x−5 and y=x2+2x−15 intersect in the third quadrant

• Pre Calculus -

y = 12x - 5. y = x^2 + 2x - 15.
Substitute 12x - 5 for y in the 2nd Eq:
12x -5 = x^2 + 2x -15,
Solve for x,
12x - x^2 - 2x = -15 + 5,
Combine like-terms:
-x^2 + 10x + 10 = 0,
Multiply each side by -1:
x^2 - 10x - 10 = 0,
Use quadratic formula to solve for x:
x = (10 +- sqrt(100+40)) / 2,
x = 10.92 , -0.916,

Substitute -0.916 for x in 1st Eq:
y = 12 * -0.916 - 5 = -16.

P(-0.916 , -16)

• Pre Calculus -

only go for it if u feel ur ready. if u can understand the ap callucus book well then u should go for it without any pressure. since school doesn't start till fall then maybe u can take a math class over the summer so if u can understand all of what I've learned or feel that you have closed that big gap that u were talking about then u can decide what u want 2 do. just follow ur heart. no one will judge u all that matters is that u r dedicated,mathematically inclined,and r not afraid 2 open new doors.