Q: 若 (-1,2) 和 (2,8) 在 y = mx + c 的圖像上, 求 m 和 c 的值?
Sol:
Substitute (-1,2) and (2,8) into y = mx + c
2 = - m + c ....... ( 1 )
8 = 2m + c ....... ( 2 )
( 2 ) - ( 1 )
6 = 3m
m = 2
2 = - 2 + c
c = 4
Ans: m = 2, c = 4
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