Answer:
Sol1 you can use "first(first+last)/2" is 138(138+1)/2 - 38(38+1)/2 = 8850
Sol2 or you can look this 39+40+41+....+100+(100+1)+(100+2)+....+(100+38) = 1+2+3+.....+99+100+100(38) = 5050+3800 =8850
Answer:
Step-by-step explanation:
( 3+1)² * 3
= 4² * 3
= 16 * 3
= 48
Answer:
x= 45
y= 18.5 (3 s.f.)
Step-by-step explanation:
Since the quadrilateral has 4 equal sides, it is a square and hence the 4 angles are right angles.
I have drawn the 2 triangles of the square separately for better understanding.
Please see the attached pictures for full solution.