Answer:
x = -3.25
Step-by-step explanation:
2/5 = 0.4
0.4x - 0.2 = -2(3/4)
-2(3/4) = -2/1 * 3/4 = -6/4
0.4x - 0.2 = -6/4
Convert to fraction
2/5x - 1/5 = -6/4
Add 1/5 to both sides
-6/4 + 1/5 = -30/20 + 4/20 = -26/20
2/5x = -26/20
Convert to decimal
0.4x = -1.3
-1.3/0.4 = -3.25
Yes
Yes it is a function, because graph is intersecting y - axis only once.
yes
x+6=3x+21
2x=-15
x=-7.50