Question

7x - 5° 7x – 4° find x

Answer 1

x = 9

Step-by-step explanation

The sum of the interior angles of any triangle is 180º. In a right triangle, the sum of the angles that are not the right angle is 90º.

This is a right triangle, therefore:

`(4x-5)º+(7x+4)º=90º`

To solve for x first we have to add like terms:

`\begin{gathered} (4x+7x)-(5+4)=90 \\ 11x-9=90 \end{gathered}`

Then we have to add 9 on both sides of the equation:

`\begin{gathered} 11x-9+9=90+9 \\ 11x=99 \end{gathered}`

And finally divide both sides by 11:

`\begin{gathered} (11x)/(11)=(99)/(11) \\ x=9 \end{gathered}`