Given a+b=7 and a-b=3, find:

3^a/3^b

27

Step-by-step explanation:

Find numbers that add up to 7.

0, 1, 2, 3, 4, 5, 6, 7

Which of those could subtract to get 3?

5 and 2

5 - 2 = 3

a = 5

b = 2

3^5 = 243

3^2 = 9

243 / 9 = 27

A=-2 and B=3

Step-by-step explanation:

Step 1) Solve the first equation for A:

a+3b=7

a+3b-3b=7-3b

a+0=7-3b

a=7-3b

Step 2) Substitute (7-3b) for a in the second equation and solve for b:

2a=b-7 becomes:

2 (7-3b) = b-7

(2*7) - (2*3b) = b-7

14-6b=b-7

14+7-6b+6b=b+6b-7+7

21-0=1b+6b-0

21 = (1+6) b

21=7b

7b/7=21/7

=3

a=7-3b becomes:

a=7 - (3*3)

a=7-9

a=-2