Answer:answer is 387
Step-by-step explanation:ok got it
Answer:
∠ 5 = 49°, ∠ 6 = 131°
Step-by-step explanation:
∠ 5 and 49° are corresponding angles and are congruent, then
∠ 5 = 49°
∠ 5 and ∠ 6 are adjacent angles and are supplementary, sum to 180° , that is
∠ 6 + ∠ 5 = 180°
∠ 6 + 49° = 180° ( subtract 49° from both sides )
∠ 6 = 131°
Answer:
bhhhhhbjfvvdfvds
Step-by-step explanation:
Answer:
a) 1+2+3+4+...+396+397+398+399=79800
b) 1+2+3+4+...+546+547+548+549=150975
c) 2+4+6+8+...+72+74+76+78=1560
Step-by-step explanation:
We know that a summation formula for the first n natural numbers:
1+2+3+...+(n-2)+(n-1)+n=\frac{n(n+1)}{2}
We use the formula, we get
a) 1+2+3+4+...+396+397+398+399=\frac{399·(399+1)}{2}=\frac{399· 400}{2}=399· 200=79800
b) 1+2+3+4+...+546+547+548+549=\frac{549·(549+1)}{2}=\frac{549· 550}{2}=549· 275=150975
c)2+4+6+8+...+72+74+76+78=S / ( :2)
1+2+3+4+...+36+37+38+39=S/2
\frac{39·(39+1)}{2}=S/2
\frac{39·40}{2}=S/2
39·40=S
1560=S
Therefore, we get
2+4+6+8+...+72+74+76+78=1560
