362 alGEbra De mystif ieD
Solve the quadratic equation by extracting roots.
25 – x^2 = 0
25 = x^2
±5 = x
Solve the quadratic equation by extracting roots.
4 x^2 = 49
x^249
4
=
x = ±^49
4
x = ±^7
2
In the next example, we need to simplify the solution. Recall that a is not
simplified if the number a has a perfect square as a factor.
3 x^2 = 36
x^2 = 12
x = ±1 2
x = ± 43 ⋅ = ±()() 43 = ± 23
PRACTICE
Solve the quadratic equation by extracting roots.
- x^2 – 81 = 0
- 64 – x^2 = 0
- 4x^2 = 100
- 2x^2 = 3
- –6x^2 = –80
✔SOLUTIONS
- x^2 − 81 = 0
x^2 = 81
x = ± 9
PRACTICE
Solve the quadratic equation by extracting roots.
- xxx^22 – 81 = 0
PRACTICE
Solve the quadratic equation by extracting roots.