Solve for x
x=7
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5\left(3x+7\right)-40=4\left(4x-8\right)+20
Multiply both sides of the equation by 20, the least common multiple of 4,5.
15x+35-40=4\left(4x-8\right)+20
Use the distributive property to multiply 5 by 3x+7.
15x-5=4\left(4x-8\right)+20
Subtract 40 from 35 to get -5.
15x-5=16x-32+20
Use the distributive property to multiply 4 by 4x-8.
15x-5=16x-12
Add -32 and 20 to get -12.
15x-5-16x=-12
Subtract 16x from both sides.
-x-5=-12
Combine 15x and -16x to get -x.
-x=-12+5
Add 5 to both sides.
-x=-7
Add -12 and 5 to get -7.
x=7
Multiply both sides by -1.
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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]
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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