|x+y| = |-8+(-13)| = |-8-13| = |-21| = 21
Answer:
Step-by-step explanation:
L
H
S
=
cos
4
x
=
2
cos
2
(
2
x
)
−
1
=
2
(
cos
(
2
x
)
)
2
−
1
=
2
(
2
cos
2
x
−
1
)
2
−
1
=
2
(
4
cos
4
x
−
4
cos
2
x
+
1
)
−
1
=
8
cos
4
x
−
8
cos
2
x
+
2
−
1
=
8
cos
4
x
−
8
cos
2
x
+
1
=
R
H
S
Again
L
H
S
=
cos
4
x
=
2
cos
2
(
2
x
)
−
1
=
2
(
1
−
2
sin
2
x
)
)
2
−
1
=
2
(
1
−
4
sin
2
x
+
4
sin
4
x
)
−
1
=
2
−
8
sin
2
x
+
8
sin
4
x
−
1
=
8
sin
4
x
−
8
sin
2
x
+
1
=
R
H
S
sin
2
x
+
cos
2
x
=
1
cos
2
x
=
1
−
sin
2
x
substitute in the equation as follows
8
cos
4
x
−
8
cos
2
x
+
1
=
8
cos
2
x
(
cos
2
x
−
1
)
+
1
=
8
(
1
−
sin
2
x
)
(
1
−
sin
2
x
−
1
)
+
1
=
8
(
1
−
sin
2
x
)
(
−
sin
2
x
)
+
1
=
8
sin
4
x
−
8
sin
2
x
+
1
Answer:
Letter c is the answer
Step-by-step explanation:
Sorry if my answer is wrong
7/8 * cm/ month * 5 months =
35/8 cm
4 3/8 cm
Answer: 4 3/8 cm