Step 1: Find the value of the puppy
The first equation shows:
+
+
= 30
Since the three puppies are identical:
30 ÷ 3 = 10
So:
= 10
The second equation is:
+
+
= 20
Substitute the puppy’s value:
10 +
+
= 20
Subtract 10 from both sides:
+
= 10
Divide by 2:
= 5
Step 3: Verify with the third equation
The third equation says:
−
= 5
Using the values we found:
5 − 10 = -5