Find a direct relationship between x and y.
-$x = 5 \sqrt { t }$ and $y = 8 t - 4$
A) $y = 200 x ^ { 2 } - 4$
B) $y = \frac { 8 } { 5 } x - 4$
C) $y = \frac { 8 } { 25 } x ^ { 2 } - 4$
D) $y = 8 \sqrt { 5 } x - 4$

Question

Quizplus · Accepted Answer

First, solve for $t$ in terms of $x$: $x = 5\sqrt{t} \Rightarrow t = \frac{x^2}{25}$. Substitute $t$ in the equation for $y$: $y = 8t - 4 = 8\left(\frac{x^2}{25}\right) - 4 = \frac{8}{25}x^2 - 4$, which matches choice C.

Find a Direct Relationship Between X and Y x=5tx = 5 \sqrt { t }x=5t​

Find a Direct Relationship Between X and Y $x = 5 \sqrt { t }$