Solve for a
a=798
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42=840-a
Multiply 24 and 35 to get 840.
840-a=42
Swap sides so that all variable terms are on the left hand side.
-a=42-840
Subtract 840 from both sides.
-a=-798
Subtract 840 from 42 to get -798.
a=798
Multiply both sides by -1.
Examples
Quadratic equation
{ x } ^ { 2 } - 4 x - 5 = 0
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Linear equation
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Arithmetic
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Matrix
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Simultaneous equation
\left. \begin{cases} { 8x+2y = 46 } \\ { 7x+3y = 47 } \end{cases} \right.
Differentiation
\frac { d } { d x } \frac { ( 3 x ^ { 2 } - 2 ) } { ( x - 5 ) }
Integration
\int _ { 0 } ^ { 1 } x e ^ { - x ^ { 2 } } d x
Limits
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