Question
2a + b = 17
a + 2b = 19
The solution to the given system of equations is (a, b). What is the value of 3a + 3b ?
- 2
- 6
- 22
- 36
The correct answer is: 36
We have two unknown variables a, b and, two equations. So, there would be exactly one solution to (a, b).
Explanations:
Step 1 of 3:
The given system of equations is,
…(i)
…(ii)
Multiplying 2 with (ii), we get
Subtracting (i) from (ii), we get
Step 2 of 3:
Putting in (ii), we get
Step 3 of 3:
Now,
Final Answer:
The value of is — 36.
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