b. How old will my sister be when my brother is 29?
c. How old will my sister be when I am n years old?
d. How old was I when my brother was k years old?
e. How much is my brother older than my sister?
Answer:
A) You would be 5
B) She would be 21
C) (Im guessing n in 9?) She would be 6 then
D) (idk what k is)
E)7 Years apart
Hope this helps
Step-by-step explanation:
Say you are X years old, your brother is Y years old, are your sister is Z years old.
Your brother is 5 years older than you can be shown as the equation:
Y = X + 5
or
X = Y - 5
Your sister is 3 years younger than you can be shown as:
Z = X - 3
or
X = Z + 3
(a) When your brother was 10, X = 10 - 5, so you were 5.
(b) When your brother is 29, X = 29 - 5, so you were 24. When you were 24, Z = 24 - 3, your sister was 21.
(c) When you were n, you can just use the equation above, but switch the variables: Z = N - 3.
(d) When your brother was K: X = K - 5
(e) Y = X + 5 and X = Z + 3
Y = (Z + 3) + 5
Y = Z + 8
So your brother is 8 years older than your sister.
35 = - 5/9x
mutiply both sides by -9/5
35*-9/5= -5/9x*-9/5
Cross out 5 and 35, divide by 5.
35/5= 7
-5/5= -1
Cross out the 5 and 5 , divide by 5.
Cross out the 9 and 9, divide by 9.
then becomes 1*1*x= x
7*-9= -63
Answer : x= -63