The correct answer to your question is "A".
Answer:
For each US dollar she gets 1.1 AUS dollars
Step-by-step explanation:
350US for 385AUS
350:385 divide by 350
1 : 1.1
A. 2x^2 - 3x + 10 = 2x + 21
2x^2 - 3x - 2x + 10 - 21 = 0
2x^2 - 5x - 11 = 0 (quadratic equation)
2x^2 - 6x - 7 = 2x^2
2x^2 - 2x^2 - 6x - 7 = 0
-6x - 7 = 0 (not a quadratic equation)
5x^2 + 2x - 4 = 2x^2
5x^2 - 2x^2 + 2x - 4 = 0
3x^2 + 2x - 4 (quadratic equation)
5x^3 - 3x + 10 = 2x^2
5x^3 - 2x^2 - 3x + 10 = 0 (not a quadratic equation)
Therefore, options a and c can be solved using the quadratic formula.
Insert 3x - 7 for y in 15x - 5y = 14
15x - 5(3x - 7) = 14
15x - 15x + 35 = 14
0 = -21
There is no solution.