Answers:
The value x is x = 15
The three sides of the triangle are
x+10 = 25
2x-5 = 25
3x-15 = 30
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Work Shown:
The curved angle markers indicate those two angles are the same measure. The sides opposite those angles are the same length. So 2x-5 and x+10 are the same value
2x-5 = x+10
2x-x = 10+5
x = 15
Once we know x, we can find the length of each side
x+10 = 15+10 = 25
2x-5 = 2*15-5 = 30-5 = 25
This also helps confirm we have the right x value (since we got the same value for each expression)
3x-15 = 3*15-15 = 45-15 = 30
This is an isosceles triangle because exactly two sides are the same length.