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\left(x+2\right)\left(x-2\right)=4\times 7
Variable x cannot be equal to -2 since division by zero is not defined. Multiply both sides of the equation by 4\left(x+2\right), the least common multiple of 4,x+2.
x^{2}-4=4\times 7
Consider \left(x+2\right)\left(x-2\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 2.
x^{2}-4=28
Multiply 4 and 7 to get 28.
x^{2}=28+4
Add 4 to both sides.
x^{2}=32
Add 28 and 4 to get 32.
x=4\sqrt{2} x=-4\sqrt{2}
Take the square root of both sides of the equation.
\left(x+2\right)\left(x-2\right)=4\times 7
Variable x cannot be equal to -2 since division by zero is not defined. Multiply both sides of the equation by 4\left(x+2\right), the least common multiple of 4,x+2.
x^{2}-4=4\times 7
Consider \left(x+2\right)\left(x-2\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 2.
x^{2}-4=28
Multiply 4 and 7 to get 28.
x^{2}-4-28=0
Subtract 28 from both sides.
x^{2}-32=0
Subtract 28 from -4 to get -32.
x=\frac{0±\sqrt{0^{2}-4\left(-32\right)}}{2}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 1 for a, 0 for b, and -32 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{0±\sqrt{-4\left(-32\right)}}{2}
Square 0.
x=\frac{0±\sqrt{128}}{2}
Multiply -4 times -32.
x=\frac{0±8\sqrt{2}}{2}
Take the square root of 128.
x=4\sqrt{2}
Now solve the equation x=\frac{0±8\sqrt{2}}{2} when ± is plus.
x=-4\sqrt{2}
Now solve the equation x=\frac{0±8\sqrt{2}}{2} when ± is minus.
x=4\sqrt{2} x=-4\sqrt{2}
The equation is now solved.