Answer:
Explanation:
He made a mistake in step one turning the 7 into a -7
- 3x + 7 = 0
Solving:
- 3x + 7 = 0 ← If the term doesn't have a coefficient, it is considered that the coefficient is 1.
+ (-3x) + 7 = 0 ← Identify the coefficients a, b, and c of the quadratic equation.
a = 1, b = -3, c = 7
x = - (-3) ±√
- 4 x 1 x 7
2 x 1
x = 3 ± √
- 4 x 7
2
x = 3 ± √9 - 4 x 7
2
x = 3 ±√9 - 28
2
x = 3 ± √-19
2
The square root of a negative number does not exist in the set of real numbers.
x = ∉ R