4.

Solve the shape equation puzzle:

A + A + A + B + B=20

B + A + A=13

3A+2B=20

2A+B=13 ➡ * (-2) ➡-4A-2B=-26

3A+2B-4A-2B=20-26

-A=-6 ➡A=6

2 (6) + B=13➡B=1

A = 6, B = 1.

Step-by-step explanation:

3A + 2B = 20

2A + B = 13 Multiply this by - 2:

-4A - 2B = - 26 Add this equation to the first equation:

-A = - 6

A = 6.

and from the second equation:

2 (6) + B = 13

B = 13 - 12 = 1.