Answer:
See images
Explanation:
Either one should work.
An isosceles triangle is a triangle where two angles are the same & the third angle is the supplement of their sum.
If you wanted the matching angles to be 70 & 70, your final angle would be 40 because:
70 + 70 = 140
180 - 140 = 40
If you wanted the supplement angle to be 70, your matching angles would be 55 & 55 because:
180 - 70 = 110
110 / 2 = 55
Hope this helped. :)