Explanation:
In isocseles triangle, base angles are equal :
base angles are angle N and angle P:
angle N=angle P
3x+17=4x+2
4x-3x=17-2
x=15
For angle N:
subtitute x in angle N
=3(15)+17
=45+17
=62
For angle P:
subtitute x in angle P:
=4(15)+2
=60+2
=62
For angle O:
sum of all angles in a triangle is 180.
angle N +angle P+angle O=180
62+62+angle O=180
angle O=180-62-62
angle O=56
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