Select all that are measures of angles coterminal with a [tex][tex]$145^{\circ}$[/tex][/tex] angle.

A. [tex]$-575^{\circ}$[/tex]
B. [tex]$-215^{\circ}$[/tex]
C. [tex][tex]$-145^{\circ}$[/tex][/tex]
D. [tex]$-35^{\circ}$[/tex]
E. [tex]$215^{\circ}$[/tex]
F. [tex][tex]$415^{\circ}$[/tex][/tex]
G. [tex]$505^{\circ}$[/tex]
H. [tex]$865^{\circ}$[/tex]



Answer :

To determine which of the given angles are coterminal with [tex]\( 145^\circ \)[/tex], we need to find angles that differ from [tex]\( 145^\circ \)[/tex] by a multiple of [tex]\( 360^\circ \)[/tex], since [tex]\( 360^\circ \)[/tex] represents a full rotation. This means for an angle [tex]\( \theta \)[/tex] to be coterminal with [tex]\( 145^\circ \)[/tex], the difference [tex]\( \theta - 145 \)[/tex] should be an integer multiple of [tex]\( 360 \)[/tex].

Let's check each given angle:

1. For [tex]\( -575^\circ \)[/tex]:
[tex]\[ -575 - 145 = -720 \][/tex]
Since [tex]\(-720\)[/tex] is a multiple of [tex]\( 360 \)[/tex] ([tex]\( -720 = 360 \times -2 \)[/tex]), [tex]\( -575^\circ \)[/tex] is coterminal with [tex]\( 145^\circ \)[/tex].

2. For [tex]\( -215^\circ \)[/tex]:
[tex]\[ -215 - 145 = -360 \][/tex]
Since [tex]\(-360\)[/tex] is a multiple of [tex]\( 360 \)[/tex] ([tex]\( -360 = 360 \times -1 \)[/tex]), [tex]\( -215^\circ \)[/tex] is coterminal with [tex]\( 145^\circ \)[/tex].

3. For [tex]\( -145^\circ \)[/tex]:
[tex]\[ -145 - 145 = -290 \][/tex]
[tex]\(-290\)[/tex] is not a multiple of [tex]\( 360 \)[/tex], so [tex]\( -145^\circ \)[/tex] is not coterminal with [tex]\( 145^\circ \)[/tex].

4. For [tex]\( -35^\circ \)[/tex]:
[tex]\[ -35 - 145 = -180 \][/tex]
[tex]\(-180\)[/tex] is not a multiple of [tex]\( 360 \)[/tex], so [tex]\( -35^\circ \)[/tex] is not coterminal with [tex]\( 145^\circ \)[/tex].

5. For [tex]\( 215^\circ \)[/tex]:
[tex]\[ 215 - 145 = 70 \][/tex]
[tex]\( 70 \)[/tex] is not a multiple of [tex]\( 360 \)[/tex], so [tex]\( 215^\circ \)[/tex] is not coterminal with [tex]\( 145^\circ \)[/tex].

6. For [tex]\( 415^\circ \)[/tex]:
[tex]\[ 415 - 145 = 270 \][/tex]
[tex]\( 270 \)[/tex] is not a multiple of [tex]\( 360 \)[/tex], so [tex]\( 415^\circ \)[/tex] is not coterminal with [tex]\( 145^\circ \)[/tex].

7. For [tex]\( 505^\circ \)[/tex]:
[tex]\[ 505 - 145 = 360 \][/tex]
Since [tex]\( 360 \)[/tex] is a multiple of [tex]\( 360 \)[/tex] ([tex]\( 360 = 360 \times 1 \)[/tex]), [tex]\( 505^\circ \)[/tex] is coterminal with [tex]\( 145^\circ \)[/tex].

8. For [tex]\( 865^\circ \)[/tex]:
[tex]\[ 865 - 145 = 720 \][/tex]
Since [tex]\( 720 \)[/tex] is a multiple of [tex]\( 360 \)[/tex] ([tex]\( 720 = 360 \times 2 \)[/tex]), [tex]\( 865^\circ \)[/tex] is coterminal with [tex]\( 145^\circ \)[/tex].

Thus, the angles that are coterminal with [tex]\( 145^\circ \)[/tex] are:
[tex]\[ -575^\circ, -215^\circ, 505^\circ, 865^\circ \][/tex]

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