15f -8f+ 13= 55
⇒ 7f+ 13= 55
⇒ 7f= 55- 13
⇒ 7f= 42
⇒ f= 42/7
⇒ f=6
Final answer: f=6~
LOL...it took me a few seconds to realize what you were attempting to express...which is the fifth root of 13 cubed...
(13^3)^(1/5) rule: (a^b)^c=a^(b*c)
13^(3*1/5)
13^(3/5)
Answer:
D. 
Step-by-step explanation:
Answer:
There are 9 quarters and 3 nickels
Step-by-step explanation:
problems used: 0.5x+0.25y=3.09
x=y+6
so substitute what x is equal to into the problem
0.5(y+6)+0.25y=3.09 <--------- distribute
0.5y+3+0.25y=3.09 <--------- Combine like terms
0.3y+3=3.09 <----------- Subtract 3 on both sided to get y by itself
0.3y=0.9 <------------ Divide by 0.3 on both sides to get what y is equal to
y=3 <-------- now substitute to find what x is equal to
x=3+6
x=9
The answers are A, D, and E.
