9514 1404 393
Answer:
(x, v) ∈ {(-3, -6), (-3, 6), (3, -6), (3, 6)}
Step-by-step explanation:
For a quick and easy answer, my "work" is to use a graphing calculator.
(x, v) = (±3, ±6) . . . . in all 4 combinations
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Add double the second equation to the first.
(5x^2 -4v^2) +2(2x^2 +2v^2) = (-99) +2(90)
9x^2 = 81
x^2 = 9
Substituting this into the second equation gives ...
2(9) +2v^2 = 90
2v^2 = 72
v^2 = 36
So, (x^2, v^2) = (9, 36). Taking square roots, we get ...
(x, v) = (±3, ±6) . . . . in all combinations
