I need help on this question

  -7/30

Step-by-step explanation:

You can use 30 as the common denominator.

  7/10 = (7/10)(3/3) = 21/30

  14/15 = (14/15)(2/2) = 28/30

Then the difference is ...

  7/10 -14/15 = 21/30 -28/30

  = (21-28)/30 = -7/30

step-by-step explanation:

0

question 1 is 8, question 2 is 9, question 3 is 24

step-by-step explanation:

now, the numbers they give you at the top are the key. from there, you just have to plug and chug! let's try 1, 2, and 3!

key: a=3, b=5, c=6

1. a+5

remember, a=3, so we plug that in to get 3+5=8

2. 15-c

c=6, so we plug that in to get 15-6=9

3. 4b

b=6, so we plug it in to get 4*6=24

time to try the rest on your own! if you put the answers below in a comment, i'll check them for you!