SOLUTION: Find the linear equation given the following information: y-intercept = -1 and the line decreases by 3 when x increases by 1

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Question 254831: Find the linear equation given the following information:
y-intercept = -1 and the line decreases by 3 when x increases by 1
Found 2 solutions by vksarvepalli, richwmiller:
Answer by vksarvepalli(154) About Me  (Show Source):
You can put this solution on YOUR website!
y-intercept = -1 means when the value of x coordinate is 0 the value of y coordinate is -1
given that the line decreases by 3 when x increases by 1
so when the x coordinate is 1 the y coordinate will be -1-3 = -4
so we have two points (0,-1) and (1,-4)
the eq is y-(-1)=[(-4+1)/(1-0)] *(x-0)
that is y+1=-3x
that is 3x+y+1=0

Answer by richwmiller(17219) About Me  (Show Source):
You can put this solution on YOUR website!
y=mx+b
b is the y intercept
line decreases by 3 when x increases by one is the slope
-3/1=3
m=slope=-3 and b=-1
y=3x-1
graph%28400%2C400%2C-10%2C10%2C-10%2C10%2Cy=-3x-1%29
3x+y+1=0
Solved by pluggable solver: DESCRIBE a linear EQUATION: slope, intercepts, etc
Equation 3+x+%2B+1+y+=+-1 describes a sloping line. For any
equation ax+by+c = 0, slope is -a%2Fb+=+-3%2F1.
  • X intercept is found by setting y to 0: ax+by=c becomes ax=c. that means that x = c/a. -1/3 = -0.333333333333333.
  • Y intercept is found by setting x to 0: the equation becomes by=c, and therefore y = c/b. Y intercept is -1/1 = -1.
  • Slope is -3/1 = -3.
  • Equation in slope-intercept form: y=-3*x+-1.