Solve for x
x=-30
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0.09\left(x+30\right)\left(x+50\right)=\left(0.3\left(x+30\right)\right)^{2}
Variable x cannot be equal to -50 since division by zero is not defined. Multiply both sides of the equation by x+50.
\left(0.09x+2.7\right)\left(x+50\right)=\left(0.3\left(x+30\right)\right)^{2}
Use the distributive property to multiply 0.09 by x+30.
0.09x^{2}+7.2x+135=\left(0.3\left(x+30\right)\right)^{2}
Use the distributive property to multiply 0.09x+2.7 by x+50 and combine like terms.
0.09x^{2}+7.2x+135=\left(0.3x+9\right)^{2}
Use the distributive property to multiply 0.3 by x+30.
0.09x^{2}+7.2x+135=0.09x^{2}+5.4x+81
Use binomial theorem \left(a+b\right)^{2}=a^{2}+2ab+b^{2} to expand \left(0.3x+9\right)^{2}.
0.09x^{2}+7.2x+135-0.09x^{2}=5.4x+81
Subtract 0.09x^{2} from both sides.
7.2x+135=5.4x+81
Combine 0.09x^{2} and -0.09x^{2} to get 0.
7.2x+135-5.4x=81
Subtract 5.4x from both sides.
1.8x+135=81
Combine 7.2x and -5.4x to get 1.8x.
1.8x=81-135
Subtract 135 from both sides.
1.8x=-54
Subtract 135 from 81 to get -54.
x=\frac{-54}{1.8}
Divide both sides by 1.8.
x=\frac{-540}{18}
Expand \frac{-54}{1.8} by multiplying both numerator and the denominator by 10.
x=-30
Divide -540 by 18 to get -30.
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