Sam has twice as many as books as Jim. If Sam gives 12 books to Jim, they will have the same number of books. How many books do they have altogether?

step-by-step explanation:

for exempl this   system of equations   y = x - 3

                                                                y = 2x - 5

look   the line : y = x -3     ( red)

                            the line : y = 2x -5 ( bleus)

example answer: "to determine if a sum is reasonable you can round each number to the nearest whole and compare the estimated sum to the actual sum."

hope this you and anyone else who needs the answer : ^)

step-by-step explanation:

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