Question

To solve the system of equations below grace isolated the variable y in the first equation and then substituted it in the second equation. What was the resulting equation?

Answer 1

Answer:

The correct option will be:   $\frac{x^2}{25}- \frac{4x^2}{49}=1$

Step-by-step explanation:

The system of equations is...........

$4y=8x ............................(1)\\ \\ \frac{x^2}{25}- \frac{y^2}{49}=1 ........................(2)$

Grace isolated the variable y in the first equation. So, she divided equation (1) by 4 in both sides. That means.......

$\frac{4y}{4}= \frac{8x}{4} \\ \\ y=2x$

Then she substituted this $y=2x$ into equation (2).

So, the resulting equation will be......

$\frac{x^2}{25}- \frac{(2x)^2}{49}=1 \\ \\ \frac{x^2}{25}- \frac{4x^2}{49}=1$

Answer 2

Answer:

It’s D

Step-by-step explanation:

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