Solve for x
x=-13
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Linear Equation
5 problems similar to:
15 - 3 x = ( 2 x + 1 ) ( 2 x - 1 ) - ( 2 x - 1 ) ( 2 x + 3 )
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15-3x=\left(2x\right)^{2}-1-\left(2x-1\right)\left(2x+3\right)
Consider \left(2x+1\right)\left(2x-1\right). Multiplication can be transformed into difference of squares using the rule: \left(a-b\right)\left(a+b\right)=a^{2}-b^{2}. Square 1.
15-3x=2^{2}x^{2}-1-\left(2x-1\right)\left(2x+3\right)
Expand \left(2x\right)^{2}.
15-3x=4x^{2}-1-\left(2x-1\right)\left(2x+3\right)
Calculate 2 to the power of 2 and get 4.
15-3x=4x^{2}-1-\left(4x^{2}+4x-3\right)
Use the distributive property to multiply 2x-1 by 2x+3 and combine like terms.
15-3x=4x^{2}-1-4x^{2}-4x+3
To find the opposite of 4x^{2}+4x-3, find the opposite of each term.
15-3x=-1-4x+3
Combine 4x^{2} and -4x^{2} to get 0.
15-3x=2-4x
Add -1 and 3 to get 2.
15-3x+4x=2
Add 4x to both sides.
15+x=2
Combine -3x and 4x to get x.
x=2-15
Subtract 15 from both sides.
x=-13
Subtract 15 from 2 to get -13.
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