The function in the slope - intercept form:
y = m x + b It passes through the points ( 2, 14 ) and ( 5, 29 ).
14 = 2 m + b
29 = 5 m + b
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b = 14 - 2 m
29 = 5 m + 14 - 2 m
29 - 14 - 5 m - 2 m
15 = 3 m
m = 15 : 3
m = 5
b = 14 - 10
b = 4
Part A: y = 5 x + 4
or: 5 x - y = 4 ( in form: Ax + By = C )
Part B :
f ( x ) = 5 x + 4
Part C :
When y = 0
5 x + 4 - 0
5 x = - 4
x = - 4 : 5
x = - 0.8
When x = 0
y = 4.
x - intercept is - 0.8 and y-intercept is y = 4. After that you can graph the function.
For the interval x ∈ ( - ∞, - 0.8 ) the function is negative and for x ∈ ( - 0.8, +∞ ) it is positive.