Question

Question 15 The perpendicular from the origin to the line y = mx + c meets it at the point (–1, 2). Find the values of m and c.

Class X1 - Maths -Straight Lines Page 228

Answer 1

∵ line OP⊥ line AB
∴ slope of OP × slope of AB = -1
here, slope of OP = (2 - 0)/(-1 - 0) = -2
slope of AB = m
so, -2 × m = -1
m = 1/2

also we have to see that ( -1, 2) satisfied the line . y = mx + c
e.g. 2 = -m + c
2 = -1 × 1/2 + c
c = 5/2

hence, m = 1/2 and c = 5/2

Answer 2

Step-by-step explanation:

see the pic ..................