Question

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

Answer 1

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.