What is the product 4n/4n-4 n-1/n+1

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Maria donates a fixed amount, a, to a charity each month. if she donates $300 in 12 months, what is the equation for a? a. a + 300 = 12 b. a × 300 = 12 c. a × 12 = 300 d. a + 12 = 300 e. a + 32 = 100

Solve the following system algebraically. y = x2 – 9x + 18 y = x – 3 a. (3,1) and (5,3) b. (3,0) and ( 4,2) c. (–4,5) and (7,–10) d. (7,4) and (3,0)