Question

Write an equation in y = mx + b form for the line graphed.

Answer 1

Answer:

y=2x-5

explanation

m is gradient so rise over run and b is the y intercept which is -5

Answer 2

Answer: y = 2x - 5

Step-by-step explanation:

Method I:

▪︎ Slope: m = (y2 - y1) / (x2 - x1)

▪︎ b is where the graph crosses the y-axis

▪︎ Points: (1, -3), (2, -1)

▪︎ m = (-1 - (-3)) / (2 - 1) = (3 - 1) / (1) = 2

▪︎ b = -5

▪︎ => y = 2x - 5

Method II:

▪︎ y = mx + b

▪︎ Points: (1, -3), (2, -1)

▪︎ System of equations:

-3 = m*1 + b,

-1 = m*2 + b

-3 = m + b,

-1 = 2m + b

m = -b - 3,

-1 = 2(-b - 3) + b

m = -b - 3,

-1 = -2b - 6 + b

m = -b - 3,

-1 + 6 = -2b + b

m = -b - 3,

5 = -b

m = -(-5) - 3,

b = -5

m = 2,

b = -5

▪︎ => y = 2x - 5