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What is the expression in factored form? -x^2 + 3x + 28 a. (x-7)(x-4) b. -(x-7)(x+4) c. (x+4)(x+7) d. -(x-4)(x+7)

1c) the number 131 is a term in the sequence defined by the explicit rule f(n)=5n-4. which term in the sequence is 131? 2a) write the first four terms of the function f(n)=n^2-1 2b) what is the 10th term of the sequence defined by the explicit rule f(n)=n^2-1 2c) the number 224 is a term in the sequence defined by the explicit rule f(n)=n^2-1. which term in the sequence is 224?

How to simply and write the answer n a whole number