How do I solve a system of equations with 3 equations and 3 variables? I have figure out to get the answer in slope intercept form, but i don't know what to do from there. here is an example
-a + 3b - 6c = 20
a + 4b - c = 15
-7b - 5c = -23

answer: two angles are called supplementary if they add up to 180°. example: the two angles (140° and 40°) are supplementary because they add up to 180°.

step-by-step explanation:

the second option

step-by-step explanation:

the correct answers are 1, 2, 4, and 5! i just got it right!