Jorge has to decide what to do with all the letters his store receives. He simply moves 90 letters from his INBOX to his OUTBOX. Now he is down to 79 letters in the INBOX and up to 156 letters in the OUTBOX. Before he moved the letters, how many were in the INBOX

169 letters

Step-by-step explanation:

Given:

He moves 90 letters from his INBOX to his OUTBOX.

After moving it is down to 79 letters in the INBOX and up to 156 letters in the OUTBOX.

Question asked:

Before he moved the letters, how many were in the INBOX ?

Solution:

Let initially letters having in the INBOX =

According to question:-

As he moved the 90 letters from his INBOX to his OUTBOX, we will write this as:

Initially letters having in the INBOX - Letters mover from = 79

Adding both side by 90

Therefore, before he moved the letters, there were 169 letters in the INBOX.

b. 2

step-by-step explanation:

the slope of a line =δy/δx

δy= y₂-y₁

δx= x₂-x₁

therefore, using the points (-2,-3)   and (3,7) we can calculate gradient as follows:

m=(7--3)/(3--2) (a number minus a negative number the sign changes to a plus)

m=(7+10)/(3+2)

=10/5

=2