Answer:
x can be 3, -3, i, or -i.
Step-by-step explanation:
If you can't find the factoring by looking at this, simplify the equation.
let
x
2
=
y
to make things easier to see
Now we have
y
2
−
8
y
−
9
=
0
See it now?
We can factor into
(
y
−
9
)
(
y
+
1
)
Now substitute back in
x
2
for
y
.
(
x
2
−
9
)
(
x
2
+
1
)
Since
(
x
2
−
9
)
is a difference of two squares,
(
x
−
3
)
(
x
+
3
)
Now we have
(
x
−
3
)
(
x
+
3
)
(
x
2
+
1
)
x can be 3, -3 for the first two parts
x
2
+
1
=
0
can become
x
2
=
−
1
Taking the positive and negative root means
x
=
±
√
−
1
Thus
x
=
±
i
in addition to 3 and -3.
Answer:
2.92
Step-by-step explanation:
Normal price
4 * 6.98 =27.92
Sale price
2 for 12.50 means 4 at 2* 12.50
2*12.50 = 25
Subtract
27.92-25=2.92
He saved 2.92
Answer:
-2
Step-by-step explanation:
hi! to find f(-3) on this graph, go to the x-value -3 and find the y-value there. when we look at -3 on the x-axis, we go down and see that there is a point at (-3,-2). therefore, f(-3)=-2.
Answer:
D: √(-4)
Step-by-step explanation:
D: √(-4) is not a real number; it's an imaginary one.