Subtract Using Additive Inverse - 7th Grade Math
Card 1 of 25
State the formula for the distance between two rational numbers $a$ and $b$ on a number line.
State the formula for the distance between two rational numbers $a$ and $b$ on a number line.
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$|a-b|$. Distance is the absolute value of the difference.
$|a-b|$. Distance is the absolute value of the difference.
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Which expression always equals the distance between $a$ and $b$: $a-b$ or $|a-b|$?
Which expression always equals the distance between $a$ and $b$: $a-b$ or $|a-b|$?
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$|a-b|$. Absolute value ensures distance is always positive.
$|a-b|$. Absolute value ensures distance is always positive.
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Identify the equivalent expression for $p-q$ using addition: $p+q$ or $p+(-q)$.
Identify the equivalent expression for $p-q$ using addition: $p+q$ or $p+(-q)$.
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$p+(-q)$. Subtraction becomes addition of the negative.
$p+(-q)$. Subtraction becomes addition of the negative.
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Find the value of $7-(-3)$ by rewriting as addition.
Find the value of $7-(-3)$ by rewriting as addition.
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$10$. $7-(-3)=7+3=10$ by adding the opposite.
$10$. $7-(-3)=7+3=10$ by adding the opposite.
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Find the value of $-5-8$ by rewriting as $-5+(-8)$.
Find the value of $-5-8$ by rewriting as $-5+(-8)$.
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$-13$. $-5+(-8)=-13$ by adding two negatives.
$-13$. $-5+(-8)=-13$ by adding two negatives.
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Find the value of $-6-(-9)$ by rewriting as addition.
Find the value of $-6-(-9)$ by rewriting as addition.
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$3$. $-6-(-9)=-6+9=3$ by adding the opposite.
$3$. $-6-(-9)=-6+9=3$ by adding the opposite.
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Find the value of $ rac{3}{4}- rac{1}{4}$ using additive inverse.
Find the value of $ rac{3}{4}- rac{1}{4}$ using additive inverse.
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$ rac{1}{2}$. $ rac{3}{4}+(- rac{1}{4})= rac{2}{4}= rac{1}{2}$.
$ rac{1}{2}$. $ rac{3}{4}+(- rac{1}{4})= rac{2}{4}= rac{1}{2}$.
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Find the value of $ rac{2}{3}- rac{5}{3}$ using $p+(-q)$.
Find the value of $ rac{2}{3}- rac{5}{3}$ using $p+(-q)$.
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$-1$. $ rac{2}{3}+(- rac{5}{3})=- rac{3}{3}=-1$.
$-1$. $ rac{2}{3}+(- rac{5}{3})=- rac{3}{3}=-1$.
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Find the value of $-2.5-(-1.2)$ by rewriting as addition.
Find the value of $-2.5-(-1.2)$ by rewriting as addition.
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$-1.3$. $-2.5-(-1.2)=-2.5+1.2=-1.3$.
$-1.3$. $-2.5-(-1.2)=-2.5+1.2=-1.3$.
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What is the distance between $-4$ and $3$ on the number line?
What is the distance between $-4$ and $3$ on the number line?
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$7$. $|3-(-4)|=|3+4|=|7|=7$.
$7$. $|3-(-4)|=|3+4|=|7|=7$.
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What is the distance between $ rac{1}{2}$ and $- rac{5}{2}$ on the number line?
What is the distance between $ rac{1}{2}$ and $- rac{5}{2}$ on the number line?
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$3$. $| rac{1}{2}-(- rac{5}{2})|=| rac{1}{2}+ rac{5}{2}|=|3|=3$.
$3$. $| rac{1}{2}-(- rac{5}{2})|=| rac{1}{2}+ rac{5}{2}|=|3|=3$.
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Compute the distance between $2.1$ and $-0.4$ using $|a-b|$.
Compute the distance between $2.1$ and $-0.4$ using $|a-b|$.
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$2.5$. $|2.1-(-0.4)|=|2.1+0.4|=|2.5|=2.5$.
$2.5$. $|2.1-(-0.4)|=|2.1+0.4|=|2.5|=2.5$.
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Identify the value of $|(-7)-(-2)|$ as a distance on the number line.
Identify the value of $|(-7)-(-2)|$ as a distance on the number line.
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$5$. $|-7-(-2)|=|-7+2|=|-5|=5$.
$5$. $|-7-(-2)|=|-7+2|=|-5|=5$.
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Find and correct the error: $9-4=9+4$. What is the correct rewrite?
Find and correct the error: $9-4=9+4$. What is the correct rewrite?
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$9-4=9+(-4)$. Must add the negative, not the positive.
$9-4=9+(-4)$. Must add the negative, not the positive.
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Which is always true for distance: $|a-b|$ or $a-b$? Choose the correct expression.
Which is always true for distance: $|a-b|$ or $a-b$? Choose the correct expression.
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$|a-b|$. Distance must be non-negative, so use absolute value.
$|a-b|$. Distance must be non-negative, so use absolute value.
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What is the distance between $a$ and $b$ if $a-b=-12$?
What is the distance between $a$ and $b$ if $a-b=-12$?
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$12$. $|a-b|=|-12|=12$ since distance is always positive.
$12$. $|a-b|=|-12|=12$ since distance is always positive.
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A temperature changes from $-3^{\circ}\text{C}$ to $5^{\circ}\text{C}$. What is the change in temperature?
A temperature changes from $-3^{\circ}\text{C}$ to $5^{\circ}\text{C}$. What is the change in temperature?
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$8^{\circ}\text{C}$. $5-(-3)=5+3=8$ degrees change.
$8^{\circ}\text{C}$. $5-(-3)=5+3=8$ degrees change.
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State the subtraction-as-addition rule using additive inverse for $p-q$.
State the subtraction-as-addition rule using additive inverse for $p-q$.
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$p-q=p+(-q)$. Subtraction equals adding the opposite (additive inverse).
$p-q=p+(-q)$. Subtraction equals adding the opposite (additive inverse).
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What is the additive inverse of a number $q$?
What is the additive inverse of a number $q$?
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$-q$. The additive inverse is the opposite sign of the number.
$-q$. The additive inverse is the opposite sign of the number.
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What is the value of $q+(-q)$ for any rational number $q$?
What is the value of $q+(-q)$ for any rational number $q$?
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$0$. A number plus its additive inverse always equals zero.
$0$. A number plus its additive inverse always equals zero.
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Find the distance between $-2$ and $5$ using an absolute value expression.
Find the distance between $-2$ and $5$ using an absolute value expression.
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$|-2-5|=7$. Calculate $-2-5=-7$, then $|-7|=7$ units.
$|-2-5|=7$. Calculate $-2-5=-7$, then $|-7|=7$ units.
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State the subtraction-as-additive-inverse rule using variables $p$ and $q$.
State the subtraction-as-additive-inverse rule using variables $p$ and $q$.
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$p-q=p+(-q)$. Subtraction equals adding the opposite (additive inverse).
$p-q=p+(-q)$. Subtraction equals adding the opposite (additive inverse).
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A temperature changes from $-3^\circ\text{C}$ to $4^\circ\text{C}$. What is the change in degrees?
A temperature changes from $-3^\circ\text{C}$ to $4^\circ\text{C}$. What is the change in degrees?
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$|4-(-3)|=7^\circ\text{C}$. Temperature rose by $4-(-3)=7$ degrees.
$|4-(-3)|=7^\circ\text{C}$. Temperature rose by $4-(-3)=7$ degrees.
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A diver moves from $-12\text{ m}$ to $-5\text{ m}$. What distance did the diver move?
A diver moves from $-12\text{ m}$ to $-5\text{ m}$. What distance did the diver move?
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$|-5-(-12)|=7\text{ m}$. Distance between depths is $|-5-(-12)|=|7|=7$ meters.
$|-5-(-12)|=7\text{ m}$. Distance between depths is $|-5-(-12)|=|7|=7$ meters.
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Find and correct the error: $8-(-2)=8+(-2)$. What is the correct result?
Find and correct the error: $8-(-2)=8+(-2)$. What is the correct result?
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$8-(-2)=8+2=10$. Error: $-(-2)$ should become $+2$, not $+(-2)$.
$8-(-2)=8+2=10$. Error: $-(-2)$ should become $+2$, not $+(-2)$.
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