Step-by-step explanation:
let no. of hours be x.
45x - 12 ≥ 117
45x ≥ 129
x ≥ 2.8667 (5sf)
therefore, 3 hours (round up to next whole number).
Topic: inequalities
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It is just asking how many meters tall are doors usually at. Clearly 30 meters isn't reasonable so just say how tall most doors are in meters.
Answer:
99/100
Step-by-step explanation:
First of all recall that
Now we we will try to apply that formula for 
and 
.
First rewrite 
Now
Answer:
Step-by-step explanation:
Divide 2 from both sides.
4x-2 = 4
Add 2 to both sides.
4x = 6
x = 1.5
Answer:
0.38268343
Step-by-step explanation:
cos(
67.5
)
Rewrite
67.5
as an angle where the values of the six trigonometric functions are known divided by 2
.
cos
(
135\
2)
Apply the cosine half-angle identity.
±
√
1
+
cos
(
135
)
2
Change the
±
to
+
because cosine is positive in the first quadrant.
√
1
+
cos
(
135
)
2
Simplify
√
1
+
cos
(
135
)
2
√
2
−
√
2
2
The result can be shown in multiple forms.
Exact Form:
√
2
−
√
2
2
Decimal Form:
0.38268343
…
