Question

the line y=mx+c passes through the points (1,1) and (2,3). find m and c using simultaneous equations.

Answer 1

m = 2, c = - 1

Explanation:

Using the point (1, 1), substitute x = 1, y = 1 into the equation

m + c = 1 → (1)

Using the point (2, 3), substitute x = 2, y = 3 into the equation

2m + c = 3 → (2)

Subtract (1) from (2) to eliminate c

(2m - m) + (c - c) = (3 - 1) ← simplify

m = 2

Substitute m = 2 into (1) for corresponding value of c

2 + c = 1 ( subtract 2 from both sides )

c = - 1