x is the number of adults and y is the number of children.
x + y = 12
<span>14x + 10y = 140
lets multiply the first equation by -10 and then add it to the second equation:
-10x - 10y = -120
</span>14x + 10y = <span>140
</span>-----------------------
4x + 0 = 20
x = 20/4
x = 5
then substitute in the original equation:
x + y = <span>12
</span>5 + y = <span>12
</span>y = 12 - 5
y = 7
therefore there were 5 adults and 7 children
Answer:
Eva swims faster than Sarah
Step-by-step explanation:
At first, they swim at different rates, but if you compare the last two (17/425 and 20/520) Eva swam the fastest.
I^63
=i*(i^(2*31))
=i*(i^2)^31
i^2=-1
=(-1)^31*i
=-1*i
=-i
