Her estimate is lower than her actual cost because her total is 72.87 she is off by 1.72 because she only added 42,17,and 12 and forgot all about adding the cent or the .60,.38,and the .89.
Answer:
0.2
Step-by-step explanation:

So y=2x is the only answer that fit y=kx, while k=2

Multiply 50 by 0.90 because you take a discount of 10% off. 1.00 = 100% 0.10 = 10% 0.01 = 1% if you multiply 50 by 0.10 instead you get the amount that is discounted instead of the new selling price.
Yes
No
Yes
No
This is because in order to be addition property of equality they have to add/ subtract by the same exact amount on both sides.