6z+43z=78
Collect like terms
49z=78
Z=78/49
Z=1.59
Hope this helps!
Ok so first just pay attention to the Mystery books and Science books.
there are 13 mystery books and 15 Science books so your answer will be two.
Hope this helps.
C, there are 3 options the first time, and after that, there are 3 options for each of those. So it would be C.
Looooking for x so the answer is
X=7
