Answer:
x=11
Step-by-step explanation:
6x-3(x+8)=9
Using the distributive property, we can turn 6x-3(x+8)=9 into 6x-3x-24=9, which simplifies to 3x-24=9 by combining like terms. Now, if we add 24 to both sides, we get 3x=33. By dividing both sides by 3, we get x=11.
Check:
66-3*19=9
66-57 does in fact equal 9.
A is NOT a function because for some values of x you get more than one y value. For example if x=2 you get 2 values for y.
b is a function because for each x you get ONLY one y
Answer:
A) 420 seconds = 7 minutes
B) 8 times
Step-by-step explanation:
A) After how many second would all three things happen together again?
Solution:
His clock ticked every 5 seconds , a tap was dripping every 7 seconds and his pet dog snored every 12 seconds. It all happens simultaneously = 5*7*12=420 seconds
B) How many times would all three things happen together again between midnight and one o'clock
Since all these events happen together after every 420 sec = 7 mins and there are 60 mins between midnight and 1 o'çlock , thus 60/7 = 8 times ....
If Sandra mixes <em>x</em> L of 65% solution with <em>y</em> L of 90% solution, then the resulting mixture has a total volume of
<em>x</em> + <em>y</em> = 500
litres, and it contains
0.65<em>x</em> + 0.90<em>y</em> = 0.75 (500) = 375
litres of alcohol.
Solve the first equation for <em>y</em> :
<em>y</em> = 500 - <em>x</em>
<em />
Substitute this into the second equation and solve for <em>x</em> :
0.65<em>x</em> + 0.90 (500 - <em>x</em>) = 375
0.65<em>x</em> + 450 - 0.90<em>x</em> = 375
75 = 0.25<em>x</em>
<em>x</em> = 300
Solve for <em>y</em> :
<em>y</em> = 500 - 300
<em>y</em> = 200
So, Sandra should mix 300 L of 65% solution with 200 L of 90% solution.