Answer:
x=1 y=7
Step-by-step explanation:
−5x+2y=9
y=7x
Substitute the second equation into the first
-5x +2(7x) = 9
Distribute
-5x +14x = 9
Combine like terms
9x=9
Divide by 9
9x/9 =9/9
x= 1
Now find y
y = 7(1)
y = 7
Step-by-step explanation:
1.
when 3 coins are flipped the following outcomes are possible
h = heads, t = tails
h h h
h h t
h t h
h t t
t h h
t h t
t t h
t t t
yes, there have to be 8 options, because we have 3 positions with 2 possible outcomes. that means
2×2×2 = 2³ = 8 possibilities.
2.
at least 2 tails means 2 or 3 t in the list item :
h t t
t h t
t t h
t t t
3.
so, 4 out of the 8 possible outcomes. the probability is then therefore
4/8 = 1/2 = 0.5
y = 4
first note that the right side simplifies to 12, equation can be written
= 12 ( multiply both sides by 0.8 )
2y + 1.6 = 9.6 ( subtract 1.6 from both sides )
2y = 8 ( divide both sides by 2 )
y = 4
