SOLUTION: The graph of linear function f passes through the point (1,-9) and has a slope of -3. What is the zero of f?

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Question 1172128: The graph of linear function f passes through the point (1,-9) and has a slope of -3. What is the zero of f?
Found 2 solutions by Boreal, math_helper:
Answer by Boreal(15235) About Me  (Show Source):
You can put this solution on YOUR website!
point-slope formula y-y1=m(x-x1) m slope (x1, y1) point
y+9=-3(x-1)
y=-3x-6
when y=0 x=-2
(-2, 0) is the function.
xgraph%28300%2C300%2C-10%2C10%2C-10%2C10%2C-3x-6%29

Answer by math_helper(2461) About Me  (Show Source):
You can put this solution on YOUR website!

y + 9 = -3(x - 1)

y = -3x +3 -9
y = -3x -6


Finding the zero:
0 = -3x -6
3x = -6
x = -2