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The sum of the interior angles, s, in an n-sided polygon can be determined using the formula s = 180(n – 2), where n is the number of sides. Benita solves this equation for n and writes the equivalent equation n = + 2. Using this formula, how many sides does a polygon have if the sum of the interior angles is 1,260°?

Verified Answer :

1,260=180(n-2) 
1260/180=n-2 
7=n-2 
n=9 
it has nine sides, hope it helps

Answer:

Equivalent equation of  \(s =180(n-2)\)  is   \(n =\frac{s}{180}+2\)

And the number of sides does a polygon have is, n =9.

Step-by-step explanation:

Given:

The sum of the interior angles, 's' in a n-sided polygon can be determined

using the formula is:  \(s =180(n-2)\)             .....[1]

where n is the number of sides.

We can write the equivalent equation of [1]

\(s = 180(n-2)\)

Divide both sides by 180;

\(\frac{s}{180} =\frac{180(n-2)}{180}\)

Simplify:

\(\frac{s}{180}=n-2\)

Add 2 to both sides of an equation:

\(\frac{s}{180}+2=n-2+2\)

Simplify, we get;

\(n =\frac{s}{180}+2\)                               ......[2]

Now, to find the value of n ;

Given: s =1260°

Substitute this value in [2] we get;

\(n =\frac{1260}{180}+2\)

or

n = 7+2 =9

Therefore, the number of sides in a polygon is, n=9