Question

HELPPP I DONT UNDERSTAND

Answer 1

`\boxed{\bf \angle B = 58^(o)}`

Explanation:

The cyclic quadrilateral sum of the opposite angle is 180°. From the given figure....

`\bf \angle B + \angle D= {180}^(o)`

Where....

~
`\bf \angle B = 3x+7`

~
`\bf \angle D = 6x+20`

• 
  `\bf 3x+7+6x+20 ={180}^(o)`
• 
  `\bf 9x+27=180^(o)`
• 
  `\bf 9x=180-27`
• 
  `\bf 9x=153`
• 
  `\bf x = \cfrac{153}{9}`
• 
  `\boxed{\bf x=17^(o)}`

Now, that we found x, let's find angle B....

• 
  `\bf \angle \: B = 3x + 3`
• 
  `\bf 3(17) + 7`
• 
  `\bf 58^(o)`

`\sf Therefore, \: \boxed{\sf \angle B = 58^(o)}`