Answer:
= 87.26 + (-25.6) + (-5.4)
=87.26- 25.6 - 5.4
= 87.26 - 31
= 56.26
✌✌✌✌✌
Solve by elimination:
S = shirt
T= tie
3s+5t=60
2s+3t=39
=
Shirt = 15
Tie = 3
Wait i think you made a spelling error, did you mean x=3?
The solution to a system of (linear) equations is the point where the graphs intersect. Consider two parallel lines. By definition, two parallel lines never intersect each other, but all pairs of non-parallel lines will eventually intersect. That means they will also have a solution.
Let's consider what makes a line parallel to another line. It basically looks identical, having the same steepness (slope), but the graph is just shifted over. That is, a parallel line would have the same slope and a different y-intercept. For our equation

, or

in slope-intercept form, a parallel line will be of the form

.
That describes the form of a parallel line, which we do not want. Any other line, however, will give a solution to our system, so we merely want a line where the slope does not equal 2.
We can have any equation of the form

.