Solve for x
x=-2
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4x+20+3\left(x+5\right)=21
Use the distributive property to multiply 4 by x+5.
4x+20+3x+15=21
Use the distributive property to multiply 3 by x+5.
7x+20+15=21
Combine 4x and 3x to get 7x.
7x+35=21
Add 20 and 15 to get 35.
7x=21-35
Subtract 35 from both sides.
7x=-14
Subtract 35 from 21 to get -14.
x=\frac{-14}{7}
Divide both sides by 7.
x=-2
Divide -14 by 7 to get -2.
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