Add and Subtract Angle Measures - 4th Grade Math
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What is the missing part if the whole is $90^\circ$ and the other part is $27^\circ$?
What is the missing part if the whole is $90^\circ$ and the other part is $27^\circ$?
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$63^\circ$. Subtract from right angle: $90^\circ - 27^\circ = 63^\circ$.
$63^\circ$. Subtract from right angle: $90^\circ - 27^\circ = 63^\circ$.
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What is the missing part if the whole is $180^\circ$ and the other part is $115^\circ$?
What is the missing part if the whole is $180^\circ$ and the other part is $115^\circ$?
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$65^\circ$. Subtract from straight angle: $180^\circ - 115^\circ = 65^\circ$.
$65^\circ$. Subtract from straight angle: $180^\circ - 115^\circ = 65^\circ$.
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What is the unknown if $m\angle AOB=x^\circ$, split into $x^\circ=3\times 10^\circ+5^\circ$?
What is the unknown if $m\angle AOB=x^\circ$, split into $x^\circ=3\times 10^\circ+5^\circ$?
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$35^\circ$. Calculate: $3 \times 10^\circ + 5^\circ = 35^\circ$.
$35^\circ$. Calculate: $3 \times 10^\circ + 5^\circ = 35^\circ$.
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What is the measure of each part if a $100^\circ$ angle is split into two equal non-overlapping angles?
What is the measure of each part if a $100^\circ$ angle is split into two equal non-overlapping angles?
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$50^\circ$ each. Divide equally: $100^\circ \div 2 = 50^\circ$.
$50^\circ$ each. Divide equally: $100^\circ \div 2 = 50^\circ$.
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What is the missing angle if $m\angle AOB=90^\circ$ and $m\angle AOC=32^\circ$ with $C$ inside the angle?
What is the missing angle if $m\angle AOB=90^\circ$ and $m\angle AOC=32^\circ$ with $C$ inside the angle?
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$m\angle COB=58^\circ$. Subtract: $90^\circ - 32^\circ = 58^\circ$.
$m\angle COB=58^\circ$. Subtract: $90^\circ - 32^\circ = 58^\circ$.
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What is the total measure if an angle is decomposed into $20^\circ$, $30^\circ$, and $40^\circ$?
What is the total measure if an angle is decomposed into $20^\circ$, $30^\circ$, and $40^\circ$?
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$90^\circ$. Sum all parts: $20^\circ + 30^\circ + 40^\circ = 90^\circ$.
$90^\circ$. Sum all parts: $20^\circ + 30^\circ + 40^\circ = 90^\circ$.
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What is $x$ if an angle is split into $x^\circ$, $25^\circ$, and $35^\circ$ with total $100^\circ$?
What is $x$ if an angle is split into $x^\circ$, $25^\circ$, and $35^\circ$ with total $100^\circ$?
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$40^\circ$. Solve $x + 25 + 35 = 100$, so $x = 40$.
$40^\circ$. Solve $x + 25 + 35 = 100$, so $x = 40$.
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What equation represents a whole angle of $150^\circ$ split into $x^\circ$ and $40^\circ$?
What equation represents a whole angle of $150^\circ$ split into $x^\circ$ and $40^\circ$?
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$x+40=150$. The sum of parts equals the whole angle measure.
$x+40=150$. The sum of parts equals the whole angle measure.
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What is the unknown part if the whole angle is $120^\circ$ and one part is $45^\circ$?
What is the unknown part if the whole angle is $120^\circ$ and one part is $45^\circ$?
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$75^\circ$. Subtract the known part: $120^\circ - 45^\circ = 75^\circ$.
$75^\circ$. Subtract the known part: $120^\circ - 45^\circ = 75^\circ$.
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What is the measure of the whole angle if parts are $35^\circ$ and $55^\circ$?
What is the measure of the whole angle if parts are $35^\circ$ and $55^\circ$?
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$90^\circ$. Add the parts: $35^\circ + 55^\circ = 90^\circ$.
$90^\circ$. Add the parts: $35^\circ + 55^\circ = 90^\circ$.
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What does “non-overlapping parts” mean when an angle is split into smaller angles?
What does “non-overlapping parts” mean when an angle is split into smaller angles?
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The parts share only a side; their interiors do not cover the same region. Adjacent angles touch at a ray but don't overlap inside.
The parts share only a side; their interiors do not cover the same region. Adjacent angles touch at a ray but don't overlap inside.
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What rule lets you add measures of non-overlapping parts to get the whole angle?
What rule lets you add measures of non-overlapping parts to get the whole angle?
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Angle addition: $m\angle AOB=m\angle AOC+m\angle COB$. When angles share only a side, their measures add to give the whole.
Angle addition: $m\angle AOB=m\angle AOC+m\angle COB$. When angles share only a side, their measures add to give the whole.
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What is the whole angle if it is split into $x^\circ$ and $x^\circ$ and $x=38$?
What is the whole angle if it is split into $x^\circ$ and $x^\circ$ and $x=38$?
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$76^\circ$. Two equal parts: $38^\circ + 38^\circ = 76^\circ$.
$76^\circ$. Two equal parts: $38^\circ + 38^\circ = 76^\circ$.
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What is $x$ if $30^\circ+x+20^\circ=90^\circ$?
What is $x$ if $30^\circ+x+20^\circ=90^\circ$?
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$x=40^\circ$. Combine known parts, then subtract from whole: $90° - 50° = 40°$.
$x=40^\circ$. Combine known parts, then subtract from whole: $90° - 50° = 40°$.
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Identify the missing angle: whole is $100^\circ$, parts are $35^\circ$, $x$, and $15^\circ$.
Identify the missing angle: whole is $100^\circ$, parts are $35^\circ$, $x$, and $15^\circ$.
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$x=50^\circ$. Subtract known parts from whole: $100° - 35° - 15° = 50°$.
$x=50^\circ$. Subtract known parts from whole: $100° - 35° - 15° = 50°$.
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What rule describes the measure of a whole angle split into non-overlapping parts?
What rule describes the measure of a whole angle split into non-overlapping parts?
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Whole angle measure equals the sum of the part measures. When an angle is decomposed, its parts add up to the whole.
Whole angle measure equals the sum of the part measures. When an angle is decomposed, its parts add up to the whole.
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What is the whole angle measure if its parts are $25^\circ$ and $40^\circ$?
What is the whole angle measure if its parts are $25^\circ$ and $40^\circ$?
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$65^\circ$. Add the non-overlapping parts: $25° + 40° = 65°$.
$65^\circ$. Add the non-overlapping parts: $25° + 40° = 65°$.
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What is $x$ if $x+25^\circ+40^\circ=120^\circ$?
What is $x$ if $x+25^\circ+40^\circ=120^\circ$?
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$x=55^\circ$. Combine known parts, then subtract from whole: $120° - 65° = 55°$.
$x=55^\circ$. Combine known parts, then subtract from whole: $120° - 65° = 55°$.
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What is $x$ if $70^\circ+x=180^\circ$?
What is $x$ if $70^\circ+x=180^\circ$?
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$x=110^\circ$. Subtract $70°$ from both sides to isolate $x$.
$x=110^\circ$. Subtract $70°$ from both sides to isolate $x$.
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What is $x$ if $x+35^\circ=90^\circ$?
What is $x$ if $x+35^\circ=90^\circ$?
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$x=55^\circ$. Subtract $35°$ from both sides to isolate $x$.
$x=55^\circ$. Subtract $35°$ from both sides to isolate $x$.
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