Question

a. 135 - 5 x (x + 4)=35

b. 25 + 3 x (x - 8)=106

c. 3\(^2\) x (x + 4) - 5\(^2\)=5.2\(^2\)

Answer 1

Answer 2

\(135-5\cdot\left(x+4\right)=35\)

\(5\cdot\left(x+4\right)=135-35\)

\(5\cdot\left(x+4\right)=100\)

\(x+4=100:5\)

\(x+4=20\)

\(x=20-4\)

\(x=16\)

b) \(25+3\cdot\left(x-8\right)=106\)

\(3\cdot\left(x-8\right)=106-25\)

\(3\cdot\left(x-8\right)=81\)

\(x-8=81:3\)

\(x-8=27\)

\(x=27+8\)

\(x=35\)

c) \(3^2\cdot\left(x+4\right)-5^2=5\cdot2^2\)

\(9\cdot\left(x+4\right)-25=5\cdot4\)

\(9\cdot\left(x+4\right)-25=20\)

\(9\cdot\left(x+4\right)=20+25\)

\(9\cdot\left(x+4\right)=45\)

\(x+4=45:9\)

\(x+4=5\)

\(x=5-4\)

\(x=1\)

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