Answer: -5100
<u>Step-by-step explanation:</u>
![\sum^4_1[100(-4)^{n-1}]\qquad \rightarrow \qquad a_1=100\ \text{and r = -4}\\\\\\S_n=\dfrac{a_1(1-r^n)}{1-r}\\\\\\\\S_4=\dfrac{100(1-(-4)^4)}{1-(-4)}\\\\\\.\quad=\dfrac{100(1-256)}{1+4}\\\\\\.\quad=\dfrac{100(-255)}{5}\\\\.\quad=20(-255)\\\\.\quad=-5100\\](https://tex.z-dn.net/?f=%5Csum%5E4_1%5B100%28-4%29%5E%7Bn-1%7D%5D%5Cqquad%20%5Crightarrow%20%5Cqquad%20a_1%3D100%5C%20%5Ctext%7Band%20r%20%3D%20-4%7D%5C%5C%5C%5C%5C%5CS_n%3D%5Cdfrac%7Ba_1%281-r%5En%29%7D%7B1-r%7D%5C%5C%5C%5C%5C%5C%5C%5CS_4%3D%5Cdfrac%7B100%281-%28-4%29%5E4%29%7D%7B1-%28-4%29%7D%5C%5C%5C%5C%5C%5C.%5Cquad%3D%5Cdfrac%7B100%281-256%29%7D%7B1%2B4%7D%5C%5C%5C%5C%5C%5C.%5Cquad%3D%5Cdfrac%7B100%28-255%29%7D%7B5%7D%5C%5C%5C%5C.%5Cquad%3D20%28-255%29%5C%5C%5C%5C.%5Cquad%3D-5100%5C%5C)
Answer:
Step-by-step explanation:
basicallyi you want to find a common denominator before you add them up. the common denominator in this case would be 20, since it's the first common multiple all of them share
50/20 plus 72/20 plus 55/20
177/20 would be your answer
PEMDAS
Parentheses, exponents, multiplication, division, addition, subtraction.
Answer: D
Step-by-step explanation:
A seems complicated and doesn’t make an sense while D is simple
Answer: (2,2), (4,2)
First, I subtracted 2y from both sides of the second equation. Then, I substituted -2y+6 in for x in the first equation (-2y+6)²+4y²=20. Then, I expanded 4y²-24y+16+4y²=20. Next, I combined like terms, and moved everything to one side 8y²-24y+16=0. Then, I factored out an 8, and then finished factoring 8(y-2)(y-1). This gives me my y-values, y=1,2. Next, I inserted each y-value into the second equation and got x=-2(1)+6 ---> x=4 (The first solution is (4,1). ) and x=-2(2)+6----->x=2 (The second solution is (2,2).
