Answer:
x = a/(a² + b²) or x = -1/a
Step-by-step explanation:
a(a²+ b²)x² + b²x - a =0
Use the quadratic equation formula:

1. Evaluate the discriminant D
D = b² - 4ac = b⁴ - 4a(a² + b²)(-a) = b⁴ + 4a⁴ + 4a²b² = (b² + 2a²)²
2. Solve for x


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Here's something I learned, if that's a go math text book the answers are always in the last couple pages of the book
Answer: $3.10 per gallon
Step-by-step explanation: 9.30 divided by 3
X = -4y+3
-x-4y = -3
________________
x+4y = 3
-x-4y = -3
0 = 0
Possible and determined system (single solution)