It's just an equation, the number you're looking for is X, and then turn the words into an solvable equation with respect to X.
7X + 3 = 39 - 2X
9X = 39 -3 = 36
X = 4
Answer: To find the third side of a triangle (there are two answers you could get), you need to use the Pythagorean formula: a^2+b^2=c^2. First answer, 3^2+5^2=c^2. Solve for c. c=5.83. The second answer, 3^2+b^2=5^2. Solve for b. b=4.
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She would have to study about 48 hours to get a score of 97.
Hopefully that helped! :)
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