Question

Please help me, i dont know how or what to do

Answer 1

From the given figure

There is a right triangle whose legs are x and 99, its hypotenuse is (x + 81)

By using the Pythagorean theorem

`\begin{gathered} x^2+99^2=(x+81)^2 \\ x^2+9801=(x)(x)+(x)(81)+(x)(81)+(81)(81) \\ x^2+9801=x^2+81x+81x+6561 \end{gathered}`

Add the like terms on the right side

`x^2+9801=x^2+162x+6561`

Subtract x^2 from both sides

`\begin{gathered} x^2-x^2+9801=x^2-x^2+162x+6561 \\ 9801=162x+6561 \end{gathered}`

Subtract 6561 from both sides

`\begin{gathered} 9801-6561=162x+6561-6561 \\ 3240=162x \end{gathered}`

Divide both sides by 162

`\begin{gathered} (3240)/(162)=(162x)/(162) \\ 20=x \end{gathered}`

The value of x is 20