Question

Do you know how to solve this?

Answer 1

X = 11

Explanation:

This triangle will add up to 180 degrees

Our angles we have right now our 42 and 78 I add those up so I know how much the missing angle will have to equal to add up with the others to equal 180 so 42 + 78 = 120

So our other angle will have yo equal 60 so we have to find out what multiplied by 7 subtracted by 17 equals 60 well 7 x 11 = 77 and 77 - 17 = 60 so x = 11

Answer 2

`x=11`

Explanation:

The sum of all the angles in a triangle is always 180 degrees.

Hence,

`(7x-17)+42+78=180`

Remove the brackets:

`7x-17+42+78=180`

Add/Subtract the numbers:

`7x+103=180`

Subtract 103 from both sides:

`7x+103-103=180-103`

`7x=77`

Divide both sides by 7:

`(7x)/(7)=(77)/(7)`

`x=11`