A plane curve is represented by the parametric equations x = −7 + 2cos θ and y = 4 + 5sin θ. Which of the following rectangular equations represents the curve?

Hello there. To solve this question, we'll have to find the rectangular equation given the parametric equations.
The parametric equations are:
[tex]\begin{gathered} x=-7+2\cos \theta \\ y=4+5\sin \theta \end{gathered}[/tex]Let's start addind 7 on both sides of the first equation and subtracting 4 on both sides of the second, such that
[tex]\begin{gathered} x+7=2\cos \theta \\ y-4=5\sin \theta \end{gathered}[/tex]Divide both sides of the first equation by a factor of 2 and the second by a factor of 5
[tex]\begin{gathered} \frac{x+7}{2}=\cos \theta \\ \\ \frac{y-4}{5}=\sin \theta \end{gathered}[/tex]Now, we simply apply the fundamental trigonometric identity:
[tex]\cos ^2\theta+\sin ^2\theta=1[/tex]such that we have
[tex]\left(\frac{x+7}{2}\right)^2+\left(\frac{y-4}{5}\right)^2=1[/tex]Square the terms
[tex]\frac{(x+7)^2}{4}+\frac{(y-4)^2}{25}=1[/tex]This is the rectangular equation we were looking for. This is, in fact, an ellipse wih center at (-7, 4) and semi-major and semi-minor axes equal to 5 and 4, respectively.
The other way we could have solved this question is by knowing when he have an ellipse with center at (h, k) and semi-major and semi-minor axes respectively equal to a and b, the parametric equations are given by:
[tex]\begin{gathered} x=h+a\cos \theta \\ y=k+b\sin \theta \end{gathered}[/tex]If the axes changes places, that is, when the ellipse semi-major axis is parallel to the y-axis, then
[tex]\begin{gathered} x=h+b\cos \theta \\ y=k+a\sin \theta \end{gathered}[/tex]And the formulas for the ellipses are the same as before
[tex]\begin{gathered} \frac{(x-h)^2}{a^2}+\frac{(y-k)^2_{}}{b^2}=1 \\ \text{ or} \\ \frac{(x-h)^2}{b^2^{}}+\frac{(y-k)^2_{}}{a^2}=1 \end{gathered}[/tex]