Answer:
C. 21.25 ( i'm assuming that C. says 21.25)
Step-by-step explanation:
Since it's an isosceles triangle, the two bottom angles are equal to one another. So 180 - 75 = 105. 105 ÷ 2 = 52.5
2x + 10 = 52.5
2x = 42.5
x = 21.25
x=21.25
triangle = 180 degree angle
knowns:
75 degrees and two opposing sides with same length have same angles
so:
180-75= 105
2(2x+10)=105
4x+20=105
4x=105-20
4x=85
x=85/4
