Solve for k
k=1
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\left(k+7\right)\left(k-2\right)=\left(k+3\right)\left(k-3\right)
Variable k cannot be equal to any of the values -7,-3 since division by zero is not defined. Multiply both sides of the equation by \left(k+3\right)\left(k+7\right), the least common multiple of k+3,k+7.
k^{2}+5k-14=\left(k+3\right)\left(k-3\right)
Use the distributive property to multiply k+7 by k-2 and combine like terms.
k^{2}+5k-14=k^{2}-9
Consider \left(k+3\right)\left(k-3\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 3.
k^{2}+5k-14-k^{2}=-9
Subtract k^{2} from both sides.
5k-14=-9
Combine k^{2} and -k^{2} to get 0.
5k=-9+14
Add 14 to both sides.
5k=5
Add -9 and 14 to get 5.
k=\frac{5}{5}
Divide both sides by 5.
k=1
Divide 5 by 5 to get 1.
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