The Square Root Property
Remember:
 Every positive number has 2 square roots – a positive one and a negative
one.
 Squaring and taking the square root are opposite operations and “undo”
each other.
𝑥 2 = 64
Example 1:
The square root of
x2 is x.
𝑥= ± 8
64 has both a + and a
– square root.
Example 2: Radials need to be simplified!
𝑥 2 = 18
𝑥 = ± √18
𝑥 = ± √9 ∗ √2
𝑥 = ± 3√2
Example 3:
(𝑥 + 4)2 = 9
√(𝑥 + 4)2 = ±√9
𝑥+4 = ± 3
𝑥 + 4 = +3 or x + 4 = - 3
x=-1
or
x=-7
You need to solve for both
the positive and the negative
square root.
The Square Root Property
Example 4:
(3𝑥 + 4)2 = 18
√(3𝑥 + 4)2 = ± √18
3𝑥 + 4 = ± 3√2
3𝑥 = −4 ± 3√2
𝑥=
𝑥=
− 4 ± 3√2
3
− 4 − 3√2 − 4 + 3√2
,
3
3
For MyMathLab you have
to write 2 separate
answers.