Using implicit differentiation, it is found that y is changing at a rate of 10 units per second.
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The equation is:

Applying implicit differentiation in function of t, we have that:

- x-values changing at a rate of 2 units per second means that

- Point Q(1,4) means that
.
We want to find
, thus:


y is changing at a rate of 10 units per second.
A similar problem is given at brainly.com/question/9543179
Answer:

Step-by-step explanation:
Let
x ----> the length of Zach's car
y ----> the length of Ginny's car
we know that
The sum of the lengths of both cars is 30 inches
so
----> equation A
Ginny's car is 2 more than 3 times the length of Zach's car
so
----> equation B
substitute equation B in equation A

You can't. If you think about the straight line on a graph, those numbers
describe a single point that the line goes through, and they don't tell you
anything about the slope of the line, or where it crosses the x-axis or the
y-axis. So I don't think you can tell the constant of variation from one point.
Answer: the bottom one
Step-by-step explanation: