Answer:
undifined
Step-by-step explanation:
slope = change in y / change in x
change in x is zero(3-3) so it's undefined
a=2,b=4. (3a+b)=3*2+4=10.
D
its the right answer bc its proportional
3:1 or 3
the left triangle is scaling up to the right triangle. 5/15 is 1/3
7/21 is 1/3
4/14 is 1/3
since it is scaling UP, the scale factor is 3:1
