Question

Find the value of'y'from the given figure

`class8`
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Answer 1

`y = 30`

Skills needed: Angle Geometry

Explanation:

1) First, let's see what we should know prior to solving.

---> We have to find the value of
`y`, and looking at that diagram, we have to create an equation.

---> The angle measure of a straight line is 180 degrees, otherwise known as a straight angle (a straight angle is 180 degrees).

---> When you add
`3y+3y`, you can set that sum equal to 180. This is because the two angles marked
`3y` added together make a straight line, which is a straight angle.

(Note: In geometry, ONE OF THE THINGS WE CAN ASSUME is that there is a straight line there.)

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2) Now, the equation would be:

`3y+3y=180`

`6y=180` --> Combining
`3y` and
`3y` (3+3 = 6)

`y = 180/6` --> Dividing by 6 on both sides, to get
`y` by itself.

`y=30` --->
`180 / 6` is 30, so
`y` is equal to 30.

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`y=30`