SOLUTION: Please help!!! Thank you!! A line passes through the point (x,y) =(-2,-3) and has a slope of -4 . Write an equation for this line.

Algebra ->  Linear-equations -> SOLUTION: Please help!!! Thank you!! A line passes through the point (x,y) =(-2,-3) and has a slope of -4 . Write an equation for this line.      Log On


   



Question 215168: Please help!!! Thank you!!
A line passes through the point (x,y) =(-2,-3) and has a slope of -4 . Write an equation for this line.

Found 2 solutions by stanbon, drj:
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
A line passes through the point (x,y) =(-2,-3) and has a slope of -4 . Write an equation for this line.
-----------------------
Form is y = mx +b ; solve for "b":
-3 = -4*-2 + b
-3 = 8 + b
b = -11
--------------
Equation:
y = -4x - 11
=======================
Cheers,
Stan H.

Answer by drj(1380) About Me  (Show Source):
You can put this solution on YOUR website!
A line passes through the point (x,y) =(-2,-3) and has a slope of -4 . Write an equation for this line.

Step 1. The slope m is given as

m=%28y2-y1%29%2F%28x2-x1%29

Step 2. Let (x1,y1)=(-2,-3) or x1=2 and y1=1 . Let other point be ((x2,y2)=(x,y) or x2=x and y2=y.

Step 3. Now we're given m=-4. Substituting above values and variables in the slope equation m yields the following steps:

m=%28y2-y1%29%2F%28x2-x1%29

-4=%28y-%28-3%29%29%2F%28x-%28-2%29%29

-4=%28y%2B3%29%2F%28x%2B2%29

Step 4. Multiply x+2 to both sides to get rid of denominator on right side of equation.

-4%28x%2B2%29=y%2B3

-4x-8=y%2B3

Step 5. Now subtract 3 to both sides of equation to solve for y.

-4x-8-3=y%2B3-3

-4x-11=y

Step 6. ANSWER. y=-4x-11

Note: the above equation can be rewritten as
4x%2By=-11
And the graph is shown below which is consistent with the above steps.

Solved by pluggable solver: DESCRIBE a linear EQUATION: slope, intercepts, etc
Equation 4+x+%2B+1+y+=+-11 describes a sloping line. For any
equation ax+by+c = 0, slope is -a%2Fb+=+-4%2F1.
  • X intercept is found by setting y to 0: ax+by=c becomes ax=c. that means that x = c/a. -11/4 = -2.75.
  • Y intercept is found by setting x to 0: the equation becomes by=c, and therefore y = c/b. Y intercept is -11/1 = -11.
  • Slope is -4/1 = -4.
  • Equation in slope-intercept form: y=-4*x+-11.
graph%28+500%2C+500%2C+-2.75-8%2C+-2.75%2B8%2C+-11-8%2C+-11%2B8%2C+-4%2Ax%2B-11+%29+




I hope the above steps were helpful. Good luck in your studies!

Respectfully,
Dr J

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