SOLUTION: Solve the system by graphing x+y=10 -4x+y=o Please help!~

Algebra ->  Graphs -> SOLUTION: Solve the system by graphing x+y=10 -4x+y=o Please help!~       Log On


   



Question 824675: Solve the system by graphing
x+y=10
-4x+y=o
Please help!~

Answer by TimothyLamb(4379) About Me  (Show Source):
You can put this solution on YOUR website!
---
x+y=10
-4x+y=0
---
copy and paste the above standard form linear equations in to this solver:
https://sooeet.com/math/system-of-linear-equations-solver.php
---
answer:
x= 2
y= 8
---
graph:
---
+graph%28+300%2C+300%2C+-2%2C+4%2C+-2%2C+11%2C+-x%2B10%2C+4x%29+
---
NOTE TO STUDENT:
the problem statement asks that we solve the system by graphing. the above computer generated graph answers that requirement.
---
if you want to solve the system by plotting the lines with pencil and paper, you need two points for each line:
---
line 1:
x + y = 10
put the equation into slope-intercept form: y = mx + b
where:
m = slope
b = y-intercept
---
y = -x + 10
m = slope = -1
b = y-intercept = (0, 10)
so we have one point: (0, 10)
get another point: set x=1 and solve: y(1) = -x + 10
y(1) = -1 + 10 = 9
so we have another point: (1, 9)
plot the two points on graph paper, then draw a line through both points, extending beyond the points
---
line 2:
-4x + y = 0
put the equation into slope-intercept form: y = mx + b
where:
m = slope
b = y-intercept
---
y = 4x + 0
m = slope = 4
b = y-intercept = (0, 0)
so we have one point: (0, 0)
get another point: set x=1 and solve: y(1) = 4x + 0
y(1) = 4
so we have another point: (1, 4)
plot the two points on graph paper, then draw a line through both points, extending beyond the points
---
answer:
find the point of intersection of the two lines. it should be (2, 8)
---
Solve and graph linear equations:
https://sooeet.com/math/linear-equation-solver.php
---
Solve quadratic equations, quadratic formula:
https://sooeet.com/math/quadratic-formula-solver.php
---
Solve systems of linear equations up to 6-equations 6-variables:
https://sooeet.com/math/system-of-linear-equations-solver.php