Find the equation of the graph:
General Equation : y = mx + b
.
Given that the gradient is 1.45
Sub m = 1.45:
y = 1.45x + b
.
Find b:
Given that x = 23, y = 48.31:
48.31 = 1.45(23) + b
b = 14.96
.
Equation of the graph:
y = 1.45x + 14.96
.
When x = 18:
y = 1.45(18) + 14.96 = $41.06
.
Answer: $41.06
