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people keep putting nonsense answers on my questionsomeone plsss help me. the answer is y=2x+16 and y=-2x-20

people keep putting nonsense answers on my questionsomeone plsss help me. the answer-example-1
User Yurez
by
3.0k points

1 Answer

26 votes
26 votes

Answer:


y=(x+8)(x+10)=x^2 + 18x + 80


(dy)/(dx) = 2x + 18


y=0 when
x=-8 and
x=-10

so the tangent slopes are
(dy)/(dx) = 2 and -2 at those x.

The lines are y = 2x + b and y = -2x + c.

We need to find b and c.

The first line must go through (-8,0) and the second one through (-10,0).

For the first line: 0 = 2*(-8) + b and b = 16.

For the second line: 0 = -2*(-10) + c and c = -20.

Explanation:

I have bunch of videos on calculus on my "Sciency Sergei" you tube channel. You are welcome to stop by :).

User Umutesen
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2.7k points