U8=15 u2+u16=26 u20=?.... Question from @larasfira

November 2018 2 5 Report

U8=15
u2+u16=26

u20=?

AMT910 U8 = 15
u2+u16 = 26

u8 = a + 7b = 15
u2+u16 = a + b + a + 15b = 26
= 2a + 16b = 26

a + 7b =15 --------> kalikan 2
2a + 16b = 26

2a + 14b = 30
2a + 16b = 26
---------------------- -

-2b = 4
b = -2

a + 7b = 15
a + 7(-2) = 15
a - 14 = 15
a = 15 + 14
= 29

u20 = a + 19b
= 29 + 19(-2)
= 29 + (-38)
= -9

1 votes Thanks 1

BringinSuroboyo $$\begin{align} \text{U}_8&=15\\15&=a+7b~...~[~1~]\\\\26&=\text{U}_2+\text{U}_{16}\\26&=a+b+a+15b\\26&=2a+16b\\13&=a+8b~...~[~2~] \end$

$$\begin{align} a+8b&=13\\\underline{a+7b}&\underline{\ =15\ -}\\b&=-2 \end~~~~~~~||~~~~~~~\begin{align} a&=\text{U}_8-7b\\&=15-7(-2)\\&=15+14\\&=29 \end$

$$\begin{align} \text{U}_{20}&=a+19b\\&=29+19(-2)\\&=29-38\\&=\boxed{-9} \end$

1 votes Thanks 1

About Us

Life Enjoy

" Life is not a problem to be solved but a reality to be experienced! "

Recommend Questions

Life Enjoy

Get in touch

Social