Sn = n/2 (a1+an)
= 8/2 (3-38)
= 4 (-35)
= -140
Answer:
a?
Step-by-step explanation:
Answer:
x=4
Step-by-step explanation:
180-58=26x+18
122=26x+18
122-18=26x
104=26x
4=x
Answer:
135 cm²
Step-by-step explanation:
The area (A) of a trapezoid is calculated as
A =
h(a + b)
where h is the height and a, b the parallel bases
Here h = 9, a = 13 and b = 17 , thus
A =
× 9 × (13 + 17)
= 0.5 × 9 × 30
= 135 cm²