silemus.

39Line through two points

Find the equation of the line through (2, −1) and (6, 7) in the form y = mx + b.

The line is y = 2x − 5. Find the slope from the two points, m = (7−(−1))/(6−2) = 2, then plug (2, −1) into y = mx + b to get b = −5. Check: 2(6) − 5 = 7 ✓.

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