Which Method Should Be Used to Solve the System? Explain $$\begin{array} { r } 7 x ^ { 2 } + 7 y ^ { 2 } = 81 \\- 10 x ^ { 2 } - 9 y ^ { 2 } = 49\end{array}$$

question 224

Essay

Which method should be used to solve the system? Explain your answer, including a description of the first step.
- $$\begin{array} { r } 7 x ^ { 2 } + 7 y ^ { 2 } = 81 \\- 10 x ^ { 2 } - 9 y ^ { 2 } = 49\end{array}$$

---

Definitions:

Kidney Stones

Hard, crystalline mineral material formed within the kidney or urinary tract.

Protozoal Infection

An illness caused by protozoa, microscopic, single-celled organisms that can be free-living or parasitic, leading to diseases like malaria and giardiasis.

Parasitic Infection

An infestation by organisms such as bacteria, viruses, fungi, or parasites that survive and thrive at the expense of a host organism.

Fresh

Recently made, obtained, or harvested; not stale or deteriorated.