A class is trying to eliminate t from the parametric equations x=t^2+3 and y=4t. Beth says that she can write t=sqrt (x-3) to eliminate the parameter. Why is this wrong?

She should have added 3 to x, not subtracted.

She should always solve for t as a function of y.

She should have taken both the positive and negative square root.

She should first substitute y for t before solving.

Question

Mathematics

Anabelle Chung

24 March, 23:19

A class is trying to eliminate t from the parametric equations x=t^2+3 and y=4t. Beth says that she can write t=sqrt (x-3) to eliminate the parameter. Why is this wrong?

She should have added 3 to x, not subtracted.

She should always solve for t as a function of y.

She should have taken both the positive and negative square root.

She should first substitute y for t before solving.

+2

Answers (1)

Know the Answer?

Cara Reeves · Answer 1

C, She should have taken both the positive and negative square roots,

Because when a number is squared, even if it is negative it can become positive,

so taking square should include + and - to the answer.