SOLUTION: 4x – 5y = -31 -12x + 15y = 93

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Question 637814: 4x – 5y = -31
-12x + 15y = 93


Answer by reviewermath(1029) About Me  (Show Source):
You can put this solution on YOUR website!
The system is dependent because if you multiply the first equation by a constant, -3 the result is the second equation. If the system is dependent then there are infinitely many solutions. The solution is (x,y) = (k, (4k + 31)/5) where k is any real numbers.
Here's the graph:
Solved by pluggable solver: DESCRIBE a linear EQUATION: slope, intercepts, etc
Equation 4+x+%2B+-5+y+=+-31 describes a sloping line. For any
equation ax+by+c = 0, slope is -a%2Fb+=+-4%2F-5.
  • X intercept is found by setting y to 0: ax+by=c becomes ax=c. that means that x = c/a. -31/4 = -7.75.
  • Y intercept is found by setting x to 0: the equation becomes by=c, and therefore y = c/b. Y intercept is -31/-5 = 6.2.
  • Slope is -4/-5 = 0.8.
  • Equation in slope-intercept form: y=0.8*x+6.2.
graph%28+500%2C+500%2C+-7.75-8%2C+-7.75%2B8%2C+6.2-8%2C+6.2%2B8%2C+0.8%2Ax%2B6.2+%29+