That sucks that that happened... let me know if i can answer any of your questions, i always try to provide a source in my answers:)
Y=-x+5
Y=2x-4
X would be your slope
Y intercepts would be (0, 5) , ( 0,-4)
Formula i used was Y=Mx+B
15% = .15
60 x .15 = 9
There are 9 puppies
the inverse of a two-by-two matrix
A=
whose inverse is
Substituting values, we get
which is not the same as matrix B. Therefore B is not the inverse of A.
We can prove similarly that A is not the inverse of B.