in the xy-plane, the line x + y=k, where k is a constant, is tangent to the graph of y=x^2+3x+1. What is the value of k?

1 answer:

3 0

When a line and a curve are tangent to each other, they are joined together by 1 point (x,y). So, you equate both equations either in terms of x or y. For this problem, let's equate in terms of y.

y = k - x
y = x² + 3x + 1

k - x = x² + 3x + 1
k = x² + 3x + x + 1
k = x² + 4x + 1

This would be the value of k. Since we are not given the common point, it can only be expressed in terms of x or y.

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fgiga [73]

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Setler [38]

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Step-by-step explanation:

Let p be the population proportion of 8th graders are involved with some type of after school activity.

As per given , we have

n= 100

sample proportion: $\hat{p}=0.84$

Significance level : $\alpha= 1-0.98=0.02$

Critical z-value : $z_{\alpha/2}=2.33$ (using z-value table)

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2 years ago

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erastovalidia [21]

1)
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Step-by-step explanation:

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