Urgent
the perimeter of △nbc is 555 m.

nb = ?

m∠n = ?

NB = 75

Angle N = 81

Step-by-step explanation:

The triangle is isosceles, which means NC and BC are equal.

(2x + 90) + (2x + 90) + x = 555

5x + 180 = 555

5x = 375

x = 75

So NB = 75

If two sides are equal, that means the angles are equal too. So angle N is equal to angle B.

A triangle has 180 degrees.

Let n represent angle N and angle B

18 + n + n = 180

2n = 162

n = 81

See below in bold.

Step-by-step explanation:

The perimeter = 2(2x + 90) + x = 555

5x + 180 = 555

5x =  375

x = 75

So NB = 75 m

m < N =(180 - 18) / 2

=  162 / 2

= 81 degrees.