Question

4) m/ABN= 20°, m/NBC = 12x + 16, and m/ABC = 14x + 12. Find m/ABC.

i got 7 the first time, but apparently, it's incorrect because the angle 14x + 12 should be 180

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Answer 1

Explanation:

12x + 16 + 20 = 180

12x = 180 - 16 - 20

12x = 144

x = 12.

14x + 12 = 180

4x = 168

x = 12.

m < ABC = 180.

Answer 2

`\sf \angle ABC = 180^\circ`

Explanation:

A complete angle is an angle that measures 360 degrees. It is also known as a full angle.

Using this:

We can say that:

`\sf m \angle ABN +m \angle NBC + m \angle ABC = 360^\circ`

Substituting given value:

`\sf 20^\circ + 12x + 16 + 14x + 12 = 360^\circ`

Simplify like terms:

`\sf 48 + 26x = 360`

Subtract 48 on both sides:

`\sf 48 + 26x - 48 = 360 - 48`

`\sf 26x = 312`

Divide both sides by 26:

`\sf (26x )/(26)= (312)/(26)`

`\sf x = 12`

Now,

`\sf \angle ABC = 14* 12 + 12 = 180^\circ`

Therefore, the measure of :

`\sf \angle ABC = 180^\circ`