Solve for r
r=5
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8+3r-15=r+8-5
Use the distributive property to multiply 3 by r-5.
-7+3r=r+8-5
Subtract 15 from 8 to get -7.
-7+3r=r+3
Subtract 5 from 8 to get 3.
-7+3r-r=3
Subtract r from both sides.
-7+2r=3
Combine 3r and -r to get 2r.
2r=3+7
Add 7 to both sides.
2r=10
Add 3 and 7 to get 10.
r=\frac{10}{2}
Divide both sides by 2.
r=5
Divide 10 by 2 to get 5.
Examples
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y = 3x + 4
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Matrix
\left[ \begin{array} { l l } { 2 } & { 3 } \\ { 5 } & { 4 } \end{array} \right] \left[ \begin{array} { l l l } { 2 } & { 0 } & { 3 } \\ { -1 } & { 1 } & { 5 } \end{array} \right]
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\frac { d } { d x } \frac { ( 3 x ^ { 2 } - 2 ) } { ( x - 5 ) }
Integration
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Limits
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