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Which ordered pair (c,d) is a solution to the given system of linear equations- c+2d=13 -9c-4d=-15

A. 90 degrees b. 45 degrees c. 30 degrees d. 120 degrees

Dexter read 11 science fiction books and 5 history books. lena read 9 science fiction books and 4 history books. compare the students’ ratios of science fiction books to history books. 1. determine the ratios’ form:    science fiction books to history books 2. write the ratios as fractions:    dexter: 115; lena: 94 3. rewrite with a common denominator. 4. compare. 5. answer the question. determine which shows the correct comparison of the ratios for this problem.