Since b is the y-intercept (where the line crosses the y-axis and x=0), we know it's 10; b or c. And slope is determined by taking 2 points on the graph (that is graphed or marked by the line) and divide the difference of the y coordinates by the difference of the x coordinates to get the answer, which is 2. So overall, the answer is 10:2, or C.
10:2, or C.
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