Sum f(k)=4k-10 for k=1 to 18.
We sum each term separately and add the sums.
![\sum_1^{18}4k=4\sum_1^{18}k=4[18(1+18)/2]=4*9*19=684](https://tex.z-dn.net/?f=%5Csum_1%5E%7B18%7D4k%3D4%5Csum_1%5E%7B18%7Dk%3D4%5B18%281%2B18%29%2F2%5D%3D4%2A9%2A19%3D684)
Therefore the required sum is 684-180=504
Answer:
m∠E = 90°
m∠F = 47°
m∠G = 43°
Step-by-step explanation:
We are given 3 angles: a 90 degree angle, and 2 unknowns. We know that all angles in a triangle add up to 180 degrees. So,
Step 1: Write out the angles equation
90 + 5x - 13 + 2x + 19 = 180
Step 2: Combine like terms
96 + 7x = 180
Step 3: Isolate the x
7x = 84
Step 4: Divide both sides by 7
<em>x = 12</em>
We take this <em>x = 12 </em>and we plug it into our original unknown angles. Thus,
Step 1: ∠F
5(12) - 13
m∠F = 47°
Step 2: ∠G
2(12) + 19
m∠G = 43°
And you have your final answers!
Answer:
108
Step-by-step explanation:
pentagons have interior angle measures of 540
540/5=108
:)
