AI Solution
Powered by Tewtor.ai
QProblem
why did you divide by 2 first?
ASolution
Dividing by 2 (the greatest common factor) is not required to solve the equation, but it makes the algebra much easier and reduces the chance of mistakes. Here’s why:
-
Simplifies the coefficients
The original quadratic isAll three terms share a factor of 2. If we factor that 2 out of the left‑hand side we get
Because the factor 2 is never zero, the equation is equivalent to
Now the leading coefficient is 1, so the constant term and the linear coefficient are small integers (3 and –4). That makes the next step—finding two numbers that multiply to 3 and add to –4—straightforward.
-
Reduces arithmetic errors
If we tried to factor the original form directly, we would need two numbers whose product is (the product of the leading coefficient and the constant) and whose sum is . The possible pairs (±1, ±12), (±2, ±6), (±3, ±4) are more numerous, and it’s easy to pick the wrong sign or pair. After dividing by 2, the product we need is just +3, and the only integer pair that works is and . -
Keeps the equation equivalent
Dividing every term (or factoring out the GCF) does not change the set of solutions because we are multiplying the entire left side by a non‑zero constant. The equationhas exactly the same solutions as
(If we divided only one term, the equation would no longer be equivalent and we would get the wrong answer—that’s a common mistake.)
-
Makes the zero‑product step clearer
After the simplification we can factor directly:leading immediately to or . If we kept the factor 2 outside, we would have
and we would still set each factor and to zero, but the extra “2” is unnecessary work.
Bottom line:
Dividing by the GCF (or factoring it out) is a convenient algebraic shortcut that leaves the same solutions while giving you smaller, easier‑to‑handle numbers. Just remember to apply the division to every term; otherwise the equation changes and you’ll get incorrect results.