Answer:
hello :
note : 1²+2²+3²+........+n² = n(n+1)(n+2)/6
Step-by-step explanation:
let : S = 1²+2²+3²+......+25²
A = 16²+17²+18²+...+25²
B = 1²+2²+3²+......+15²
S = (1²+2²+3²+....+15²) + (16²+17²+18²+...+25²)
calculate : S for : n = 25
S = 25(26)(27)/6 = 2925
calculate : B for : n = 15
B = 15(16)(17)/6 = 680
so : S = B + A
A = S - B = 2925 - 680 = 2245
Answer:
16 pounds
Step-by-step explanation:
1/5 is just 20% percent as a fraction so just multiply 80 by 205 to get 16.
Answer:
B. isosceles, obtuse
Step-by-step explanation:
An isosceles triangle has 2 congruent sides and the is an obtuse angle.
Answer:
the answer is A. hope this helps!
Four multiples by a number will equal negative eight