How do you solve the system by graphing #3x + 5y = -8# and #8x - 2y = -6#?

1 Answer
May 18, 2017

Answer:

Point of intersection #->(x,y)=(-1,-1)#

Explanation:

Given:

#8x-2y=-6" "......................Equation(1)#
#3x+5y=-8" "......................Equation(2)#
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

#color(blue)("Consider "Equation(1))#

#color(brown)("Showing all the steps")#

Add #2y# to both sides

#8x=-6+2y#

Add 6 to both sides

#8x+6=2y#

Divide both sides by 2

#4x+3=y#

#y=4x+3" ".....................Equation(1_a)#
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
#color(blue)("Consider "Equation(2))#

Using the same processes as above. I have and NOT showing all the steps:

#y=-3/5x-8/5" ".......................Equation(2_a)#
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
By substituting values for #x# build a table of values for each equation. You only need as a minimum 2 points for each line. 3 is better as it forms a check. You lines should pass through each point.

Plot your lines and read the value of the graph.

Tony B